This is a repository for major, life-altering mistakes that you or others have made. Detailed accounts of specific mistakes are welcome, and so are mentions of general classes of mistakes that people often make. If similar repositories already exist (inside or outside of LW), links are greatly appreciated.
The purpose of this repository is to collect information about serious misjudgements and mistakes in order to help people avoid similar mistakes. (I am posting this repository because I'm trying to conduct a premortem on my life and figure out what catastrophic risks may screw me over in the near or far future.)
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.