Mistakes repository

Placing zero value on the ability to look, dress, and act like a non-nerd. I seriously overestimated the effort and underestimated the benefits.

Not precommitting to be on my own before making a major life decision.

I once bought something in an New York shop through high-pressure sales. I looked at it and said something about how I would like to have it but I couldn't nearly afford it, and he asked me how much I would pay for it. Foolishly, I named a price; he looked insulted and said that it was far too low. I tried to explain that that was what I meant, that I couldn't afford it at any reasonable price, but he skilfully turned it into haggling, and I walked out with the thing and considerably poorer. I then resolved never to buy anything expensive without leaving the shop first, so I could just walk off if I changed my mind.

Many years later, I met up with my girlfriend's girlfriend for dinner and drinks so we could discuss whether it would work for her to move in with us. There were a lot of warning signs that it wouldn't, to say the least. I pressed her on things that were worrying me, and got wholly unsatisfactory answers. But we very often had good and enjoyable conversations, and this was one of those times. So at the end she sort of said "OK, that's all great, shall we announce online that I'm moving in?" and it wasn't easy to say no. The result was very costly for all of us; it was definitely the biggest and most predictable mistake of my last decade.

Going into such a conversation another time, I'd have said well in advance that I wouldn't be making any decisions until the next day, when I was on my own. I think there's every chance that that simple precaution would have saved untold suffering and money for all concerned.

Rationalising my feelings of social anxiety by adopting the view that I should not be socialising with my "intellectual inferiors" anyway: one must choose to be social or intelligent. When I entered university and met people I considered intellectual peers I was hardly able to socialise with them either because my social skills were so inadequate. Post-university it still took me a few years working at a low-paid job with a forced social element (working at a shop in a shopping mall) to kickstart my social development.

I once thought I'd skip learning to cook, thinking I'd specialize in something else and trade money for someone else's cooking. I've since learned to cook moderately well, and there are benefits:

• Much better control of your nutrition
• It impresses people; I can create dinner dates and dinner parties
• It's tradable; you can swap your cooking for people doing other chores or buying food
• Cooking is an activity with enjoyable depth, satisfying geeky tendencies to learn
• Cooking is easy to learn, giving you success spirals
• You can influence the nutrition of those close to you

Being too ambitious in university and trying to do a three-year degree in two years, for essentially no real reason. Getting a burnout, recovering somewhat, and then trying to catch up by doing a lot of extra work each semester. Being able to sustain this for about three quarters of each semester, until I'd end up dropping several courses and accomplishing less than I would have if I'd taken a lighter course load from the start. Essentially repeating this until I'd finally finished my three-year-but-going-to-try-doing-it-in-two-years degree over a period of five years.

Be careful about how much you invest in a relationship. Whatever you might think at any moment, the probability that it will end in the future are relevant. I happened to make several life-changing choices in order to optimize the relationship with my former girlfirend, since we had been together for a long time and thing were sitll looking awesome. She dumped me abruptely, and I found myself navigating into a huge void of lost friends, lost hobbies, and a job that I like, but it's not the one I had always wanted to have (and had, before changing for the sake of the relationship).

Starting university with chemistry rather than computer science. Started on chemistry because I'd really enjoyed it at school, because my teacher was fantastic; realised I didn't actually like it at all. If I'd started on comp sci (and this was in 1985), I'd have done well, I'd have had much more money earlier, and my ridiculously intensive personal hobbies wouldn't have been affected.

tl;dr unexpectedly hazardous: good teachers.

1 I would say "Marrying the wrong person," but phrased that way, it's not really useful as a warning.* So let's go with "Marrying for the wrong reasons (e.g. because then low self-esteem and limited prior success with the opposite sex led me to settle far too quickly despite what should have been obvious warning signs). The emotional and financial consequences were catastrophic -- a lost decade of life, basically, And due having to children, another decade of not completely being able to escape their malign influence even after divorce.

*The more specific form "Not realizing I was marrying a borderline may be somewhat more useful. I know I've seen other Lesswrongers talk about similar issues, though I think they escaped before marriage and children.

2 Not actually doing any networking in college/grad school despite attending very prestigious institutions (due to introversion and cluelessness about the usefulness of this)

3 Not doing anything to deal with social anxiety much earlier, thus missing out on so many different opportunities.

In fairness to me, I'm older than the median LWer, and the Internet was a lot less helpful for finding the answers to life problems then than it is now.

Not seeing medical professionals as soon as medical problems arose. I now live with (likely) permanent chronic pain which may well have been preventable were the causes addressed at an earlier date.

The mental model that states that since all past problems have been inconsequential, all future problems must therefore be inconsequential is a problem here. Holding that mental state (my past problems have evaporated without issue, therefore my future problems will do likewise) is problematic because most people have not experienced enough major problems to draw on a meaningful sample size here.

Mistake 1: Trying to convince others that I know more than I really do.

Mistake 2: Thinking that I actually know more than I do.

Not stepping back and thinking strategically about where to go and why before beginning a PhD program.

Because of a deteriorating relationship and problems in my current lab, I felt completely overwhelmed by the prospect of choosing a PhD. I was being told by my superiors that I had loads of potential and therefore had to get into the most prestigious institute possible. I therefore copped out of the difficult task of doing a PhD and essentially allowed my supervisor (who I knew was incompetent) to choose one for me. I never asked myself if I really wanted to do the research I was being pushed towards, if labwork was a rational choice for someone with my skillsets, or, more importantly, if I wanted to do a PhD at all.

Imagine my embarrassment when I start reading lesswrong and discover that stories like this about grad school are a stock example of irrational behavior...

Several popular comments say something to the effect of "I was too arrogant to just get with the program and cooperate with the other humans".

The biggest of my own arrogant mistakes was not taking CS/programming very seriously while in college because I was dead set on becoming a mathematician, and writing code was "boring" compared to math. Further arrogance: I wasn't phased by the disparity between the number of graduating Ph. D.'s and the number of academic jobs.

I found out in grad school that my level of talent in mathematics, while somewhat rare, was certainly not so exceedingly rare that real world considerations would not apply to me.

I've since changed my attitude, and I'm working on fixing this mistake.

• Not taking the wisdom of nature seriously and, in particular, failing to appreciate the possibility that a considered intervention (e.g. polyphasic sleep) might do more harm than good.

• Failing to do all sorts of things that I would have enjoyed merely because they involved some trivial inconvenience.

Majored in philosophy. I don't think I learned much worthwhile and it's makes it harder to get a job.

Not taking risks of audio noise exposure seriously. Hearing loss is gradual, and tinnitus often starts as a temporary thing, so it's very easy to accumulate major damage before you realize it's a problem.

Taking advice because it's consistent and sounds reasonable, rather than because it's worked in practice.

-Taking the non-thinking NPC college route (going to whatever school was close enough to commute to, majoring in classes you thought were easy or letting your family influence your decision too much)

-Getting married extremely young because you think (probably correctly) that you can't support yourself, and then staying married much longer than you should have for the same reasoning (probably incorrect, by then).

-Spending most of college trying (and failing miserably) to take a large course load before realizing that you really just can't do it, and the only way for you to actually succeed is to only take two or three classes at a time so that you can do perfectly in all of them (i.e. stop trying to fight your perfectionism if it's causing you to fail, and just give in to it).

-Waiting much too long to start on a career track.

• Failing to learn one's social norms quickly enough, and failing to make any falsifiable tests as to whether I was making mistakes. I was nearly asocial in elementary school, middle school was just weird, and then high school was this horrible mess of thinking people were being freaked out by me, or avoiding me, or not avoiding me, or literally anything. In reality, lots of people loved me and I didn't need to fear or be awkward about asking favors of people or asking to hang out with them.

• Buying big-ticket items such as computer equipment by numerical stats only. Compactness, physical construction quality, compatibility, and battery life (which is remarkably often not really rated, or degrades significantly) may be as important or more important than non-numerical quantities. For the specific example of laptop computers, this means to go for low-end Macs, business-level computers, and if you desire Linux, Lenovo Thinkpads. And the worst part is that I didn't end up spending that much less than I would have for something with much better construction quality, etc.

• Not having any friends or interests outside of STEM (during university), or even outside a very specific nerdy mindset.

A selection of my top few regrets:

• Getting into a relationship I didn't know how to get out of. (Result: I feel like years of my life have been wasted, and I was seriously distracted during an important period of my education.)

• Not learning to code in college. (Result: Hard to say at this point, but probably financially costly and I'd feel much better about myself if I'd graduated with a marketable skill. It's definitely easier to learn when there's some time pressure and also TAs who can help you figure things out.)

• Not taking advantage of moderately frightening opportunities that I thought would remain open for years but in fact closed within weeks. (Result: Details are personal, but I believe it contributed substantially to mistake #1.)

An interesting subset is the bad decisions you made that you knew at the time were bad, not just in retrospect, but did it anyway.

-Thinking I should follow advice I got from older respected people. The best advice I've ever had is that "lots of advice is BAD advice, or at least bad for you." I wanted to be open to criticism, and I'm into self-improvement, so I used to take advice really seriously when it came from a remotely intelligent source. Lots of it was contradictory, lots of it didn't apply to me and my specific situation and personality, lots of it arose from the special particularities of the advisor, and lots of it was just people saying vague things that sounded wise to feel like they had something to offer me. Instead, I started taking surprising/unusual advice (which really is the only useful kind, in my opinion) seriously only when it came from someone who knew me and my situation well, I understood the reasoning behind it, and I had gotten similar second opinions from other respected sources.

(Also, asking the advice of people I respected at a young age (12-19) instead of going online to find solid, well-tested, data-supported strategies to deal with my problems and questions).

-Doing research in a field that didn't interest me early on because I felt like I should be doing research of some kind, thought it would gain me prestige, and thought it would not be overly time-consuming. In reality, it probably did get me some limited prestige, but the opportunity cost was exorbitant. It was extremely time-consuming, and additionally added to feelings of stress, meaninglessness, and frustration at that time in my life.

-Not getting on okcupid for a long time because of the social stigma in my social circle. I've met so many amazing people on that site, including my current SO, plus it exposed me to a wider community, taught me what more people outside my community like/want/act like, and built my confidence about my ability to find love and romance if my current relationships fell through. This helped me become choosier (and thus more able to pick out smarter, kinder people I enjoyed more) and less anxious about dating in general (which made me a kinder, more fun person to be around).

I don't know how to phrase it best so it fits here, but I feel it does, because it complicates my life regularly and therefore is pretty major: Not sticking to very beneficial routines that I know to be highly useful for my overall functionality in the short term and neccessary in the long term.

I know that I am happier and better-functioning when I regularly make journal entries and meditate. I am more productive at work, and I have more energy in my free time for other projects. Yet, I'm in a cycle where, when everything is going very well, I neglect both activities. Everything continues to go well for a while, then I get unbalanced, less energetic and overall less happy and productive, and only then do I remember that I already know what I can do to improve my situation.

For example, I neglected journal-writing and meditation in the past three month, which was a critical time because this left me with little energy to learn for a test (I'm currently doing a second M.Sc. to improve my chances of entering the economic sector I'm especially interested in). It won't have any unalterable consequences yet - if I fail on Friday, I can repeat the test next year, without having to study longer than intended - but it will make things more difficult and time-intensive next year, because I will have to prepare for the repeat tests as well as the tests scheduled for next semester. And I fear it's only a matter of time till this leads to bigger consequences (Seriously affecting job performance, for example).

20 years of organized religion. Let me count the ways in which this is harmful.

• 20 years of religiosity. (Oof!)
• Quitting programming after 1 yr due to boredom.
• Not studying math and science early (because: religiosity).
• Going to college.
• Not moving to the Bay Area at age 18.

I have made several serious misjudgements that are all instances of mistaking "I find this easy" for "this is easy in some general sense". Finding something easy is indeed evidence in favour of the thesis that it's easy, but it is also evidence that you are particularly good at it. I've mistakenly ignored the latter.

Not autobiographical, all but one are people I know or have known personally. Which is not to say I have avoided all of these mistakes, but none of this is telling my own story. The ones about reasons for choosing college majors are speculation about other people's motivations, but are obviously mistakes whether they are the true reasons for people's bad choices or not.

Waiting through several years of depression and suicide attempts before telling anyone or getting it treated.

Not living on campus while you attend college, and also not having a car. (Edit: it has been pointed out that this often isn't that big a mistake. These are the circumstances under which I would call this a big mistake).

Not getting good enough grades in high school to get scholarships in college.

Going several thousand dollars into debt to pay for your first year of college classes, and then dropping out.

Living under parents who expect you to do several hours of manual labor per day while attending college, depending on them for rides to and from college, while sinking most of your income and lots of your time into construction of a cabin, far from said college in your hometown, which said parents own the deed to, while you do not have a car.

Registering as an engineering/nat science major in college when you are not good at math or cannot deal with hard work.

Having babies before you have finished all the formal education you want to get.

Not taking the time to apply for good internships during college.

Not taking enough time to apply for colleges during high school.

Not paying attention to deadlines for fellowship and grad school applications in the fall a year before school starts.

Not taking the GREs soon enough before you need to submit scores that you can retake them if you need to.

Not registering far enough in advance as an engineering major to take the Fundamentals of Engineering exam before you graduate (If it's a requirement at your school).

Choosing a major in college based on misconceptions about what you will actually be studying and/or what work that will qualify you for.

Choosing a major in college based on the difficulty during college, and not the effects it will have on the rest of your life.

Choosing a major in college because your friends have chosen the same one.

Choosing a college because your friends have chosen the same one.

Wanting to go into a technical field in college, but not taking the highest math and science classes your high school offers, and being forced to make them up in college (Not very life-altering, but can set you back a year).

The numerous mentions of soured relationships make me think that "not knowing some basic relationship failure modes, or not weighting the possibility that they will happen strongly enough" is another metamistake.

Perhaps not truly life-altering, but I'm currently somewhat regretting not having taken a formal course in Computer Science to complement my physics education. The problem with being self-taught isn't so much that there are gaps, but that you don't know where the gaps are, and you don't have the language to discuss (or Google) them easily.

Turning from myself to others, I see many physics graduate students who would benefit vastly from just one introductory formal course in programming - not computer science per se, just basic programming concepts. Flow control, scope, pass-by-name versus pass-by-reference, what's an object, what's the difference between a class definition and an object instantiation, what does it mean to call a method on an object. These are all things that it's possible to pick up by osmosis, especially for people as smart as physics grad students tend to be (although, admittedly, this is not an invariable rule...), but you can flounder quite a bit in the year it takes you to do so. A quarter, even a semester, of organised instruction would save time overall.

Not making a special effort to move out of home when I started university.

Allowing akrasia to prevent me from applying for a single graduate position at any of the many companies that were hiring Computer Science graduates in my final year of study.

Allowing akrasia to prevent me from joining any clubs or associations at university.

Not getting a minimum-wage job for work experience when I was still young enough that the minimum pay for me was lower, giving me a competitive advantage.

Every time I lie, I regret it a little bit, as I wonder whether the long term trajectory of my life would have been different had I been totally truthful instead of 'polishing' the truth.

Not flossing for years. Once it is a habit not flossing will seem gross to you. Knowing that your future self will feel this way you should feel this way now.

That thing I'm going to do next month that I don't even know about yet.

Taking about twice as long as I could have at the university while it was obvious the entire time that I wasn't putting the necessary work into learning the heavy math I would need if I wanted to be a successful grad student. Should've failed fast with the research career aspirations and graduated as fast as I can. (You pick your own course load and usually work up to a Master's degree in Finnish university. There are grades, but generally only graduate studies programs care about them, so if you know you'll go to industry, you can load up on the courses and treat any passing grade as good enough.)

I wouldn't say any of these have been terminal, but I might reconsider some of the following things I did, if given the option:

• Chose a major based on what I felt like spending four (...okay, five) years doing, rather than on what I thought I might enjoy spending any significant portion of my working life doing. In fairness to my past self, I don't think I had enough information when I was 18 to have made anything like an accurate guess, but maybe it was also a mistake to fail to attempt a solution to that preliminary problem.

• Moved in with a significant other even though I didn't want to. (For the record, it turned out great! But there were some hair-raising moments for a while.)

• Stayed in a job that sucked and didn't have any obvious prospects for improvement. Didn't try very hard to find a new job while I was there.

The overarching theme here: not knowing, not trying to figure out, not asking for, and not making/executing plans to achieve what I really wanted.

As alluded to in other comments, another interesting question is: given your past mistakes and your present circumstances, what do you expect your next "major life-altering mistake" will be?

Potential examples: continue to play football despite repeated concussions, getting together with yet another abusive boyfriend, relying on magical free will to get you through college until finally burning out and dropping out.

1. Not figuring out what I wanted to do before I finished college.
2. Got a lot of sunburns between the ages of 12-20.
3. Didn't take speech therapy seriously as a kid, had to work much harder later.

It's still up in the air but arguably dropping out of high school and then community college.

Trying to avoid personal vices by not acting or thinking like the people who had the vices I wanted to avoid. For example, wanting to be a great scientist, and suppressing this desire without realizing that it wasn't actually possible for me to aspire for one thing, dislike m motivation for it (fame and accomplishment), and try to come up with a better one- the actions conflict with each other, yet I really did think that the only reason I wasn't pursuing that path already was due to a disruptive home life. This is probably true, but to this day I can't tell if I was flinching away from the fact, or if I was that distracted that I wasn't thinking deeply enough.

Trying to extrapolate cognitive science and theory of mind without assistance (or at least familiarizing myself with Egan's Law) by observing and altering my thought process, and subsequently having a 3-month long dissociative episode involving many suicide hotlines, a significantly lowered GPA, and a "ruined before it started" romance.

First, excellent idea!

Second, where do I start... Am I the only one who can list at least half a dozen life-altering sub-optimal decisions without pausing to think? Nothing catastrophic, though. I'll only mention a few school-related ones.

Undergrad: yielding to pressure to go for a comp. eng. degree instead of physics and not talking a chance to switch when one was available. Sure, employment options and salary are way better in comp. eng., and I never hated the work. But I will never find out whether I could have been a top x% scientist, rather than a somewhat-better-than-average programmer.

Grad school:

• Waiting too long before going back to school. Could and should have done it 8-10 years earlier. Bad for several reasons: older means harder to learn and less competitive for postdoc positions, less mobile means fewer school choices, used to higher income means harder to downgrade. "A luxury, once sampled, becomes a necessity".

• Overestimating my mathematical abilities when picking a PhD research topic (and a supervisor) after a successful and enjoyable Masters. As a result, I ended up with a mediocre thesis and no easy career path in academia. Aggravated by occasional professional and personal conflicts with the supervisor, who was not known for promoting their grad students to begin with. Watching someone with a very similar skill set do extremely well after picking a less risky path shows what could have been.

Majored in Environmental Science; while it's not useless with respect to finding work, I feel that something like Chemistry would have had similar value for most of the same jobs, whereas Environmental Science is not valuable in all contexts that a major like Chemistry would have been.

Plus, it tends to lump me in with environmental activists, signalling-wise, while I am firmly of the opinion that if we actually want to solve most environmental problems, our solutions will have to be technological, not social.

• Not living on campus with friends during college
• Taking too many high-level math classes in my first year of college (including a really dense graduate abstract algebra course)
• Not getting therapy while in college (rectified during grad school)
• Not applying for internships in college (also rectified during grad school)
• Turning down a promising summer research project right before my PhD. I thought that summer was a bit overloaded and I was going to do research during the PhD anyway, but it took 1.5 years of classes and qualifying exams before really getting started with research, so in retrospect I should have dropped other things from that summer instead.
• Choosing a (somewhat) wrong field for grad school - I went into stats, but the main part of stats that interests me is machine learning, so I should have probably gone into CS.

1. Not realizing that I was in pain (physical/mental/etc.) on a regular basis and dropping everything (or at least, as much as possible) and tackling them.

2, Thinking to myself that I would be able to do better/etc. on situation X in the future despite not changing anything or thinking hard about why situation X went badly in the past.

Two mistakes from when I was figuring out where to go for my PhD:

• Not applying to more PhD programs. I limited myself to four because (a) I only wanted to apply to strong programs in my field, (b) I was very picky about location, and (c) I was too confident. Ultimately, this worked out okay, but I now regard the decision as arrogant and risky.

• Not validating code and data used to decide which PhD programs to apply to and which PhD program to choose. As part of these decisions, I collected data about many things. For one of the more important things, I wrote a web scraper to collect data and processing scripts to distill the data into something useful. In this case, the result was a table ranking cities in a particular quantity. Unfortunately, some data corruption combined with sloppy coding seriously skewed my results. I did not notice this problem until well past when I made my decision. After restoring a backup of the data and writing a validation script to check the data's quality, I noticed that the city I selected actually was among the worst in this particular quantity, not acceptably worse than average as I had thought before. Oops. Software Carpentry has some good notes about how to handle data like this. (This point has intentionally been written abstractly because what the data represents is not important.)