I regret not having:<p>- Practiced better financial behaviors. I'm nearly 40 and have a negative net worth (lots of debt, no assets, no retirement, only part-time employment). I really need to sort that out instead of wasting time on HN, lol<p>- Learned to mountain bike/kayak/climb/ski/do martial arts sooner (lots of fun, but my old body struggles and all the joints ache). I still do all those things, just at a lesser intensity. I wish I started much younger.<p>- Taken better care of my teeth and listened to my dentist's advice more thoroughly (ouch!)<p>- Put more energy into side passions outside of work. Had a tendency to float around between hobbies, without much devotion/commitment, so never really developed any of them meaningfully<p>What I am really GLAD I did:<p>- Learned to be happy while single (super important!)<p>- Moved around a bunch, both geographically and between jobs. Learned a lot along the way and met all sorts of interesting people and went to a lot of awesome places. Not exactly digital nomading, just uprooting every few years.<p>- Tried out a lot of different events / subcultures, from dance to martial arts to board games to dev meetups to sports groups to music concerts etc. Good way to learn what kind of activities and people I actually enjoy.<p>- Met many people, friends and dates both, but treated them all with respect and formed lasting relationships<p>- Maintained a relatively OK exercise & diet pattern (not great, not terrible). Slightly overweight with some minor chronic health issues but nothing major yet, thankfully<p>-----------------------<p>Overall, I think the most valuable lesson for myself has been "It's OK to fuck up, as long as you learn from it... eventually. Sometimes it takes two or three tries, but just keep trying to do it better than last time. You'll get there... someday." I'm not necessarily a more <i>effective</i> person than I was in my 20s, but I'm an infinitely <i>happier</i> one now.