I think that's the kind of attitude that sometimes leads to the worst midlife crisis. Because you're holding yourself to an extremely high standard: for your life to be perfect in all aspects (by your own judgement) by ~40. Personally I learned to battle mid life crisis with a dose of humility (I haven't figured it all out, and that's exciting) and humor.

I'm not expecting perfection. But I am treating my life a lot like navigating in a sailboat. You have to have your eye on the horizon and use the stars the guide you. You can't always reach your destination in a straight line, but you also shouldn't be way off course.

No one has 100% agency, you don't always have a rudder, sometimes the wind capsizes your boat and you drown to death. Sometimes you had to compromise so much that the end result doesn't satisfy you. That's what a midlife crisis is after all. A lot of people did their best, and are still unhappy with the outcome because luck plays a huge role in life.

Some people don't even get boats my friend, they have to try and succeed on a plank of driftwood. I hope you don't have a midlife crisis either, but chances are pretty high your not going to end up exactly where you thought you would be, and hey maybe that ends up being a good thing. Maybe your horizon was okay but you actually lucked into something you loved more.

Yeah but the point about the crisis is realising that maybe your chosen destination was a mistake you made based on incomplete information, or else you've arrived and it's not what you imagined it would be so now what do you do?

But you've figured out what 20 year old and 30 year old you wanted, not necessarily what 40 year old you wants.

I was shocked by the cookie cutter midlife crisis I had upon hitting 40 despite thinking I was doing all the right things before that.

My decision making has largely been driven by looking at those older than me and asking myself if that’s the type of life I want to live. If the answer is yes, then I use those people as role models. So I think my optimization strategy has been on a longer time horizon than just what I want in my 20s or 30s.

This approach seems wise, and to an extent I've tried to follow it as well. "Learn from other people's mistakes" - for me this has always seemed natural, and in a sense I've been fortunate to have some good learning opportunities.

One complication is that we all follow different paths through life; those older people didn't get to where they are by going further down the same path you're on.

Did you ask those people whether they have the same desires in their old age as they did when they were younger?

EDIT: my question comes across as combative and snarky. I honestly hope your strategy works out. Just for me the life I now enjoy in my 40s is not one I ever thought I'd want and it was a rough fews years getting over that.

I didn't take it as snarky. I could write a long essay on how I've used the experiences of those older than me to make decisions, but I'll spare you the diatribe. One strategy, though, is to ask people about their experiences. Do you mind sharing what was rough about those years in your 40s?

I had strong convictions about the things I would be doing and achieving in my 40s. The responsibilities that I actually had in my life were in direct conflict with that though. Initially I tried to do it all and just felt like a failure on all fronts. It wasn't until I accepted that I had way less control in life than I imagined that I was able to let go of the things I thought I should be doing and instead embrace and enjoy the things I needed to be doing.

The assumption here is changing course is a bad thing? And what defines changing course?

Also how do you know what your 40 or 60 year old brain will think when you are 20?

If our brains thought the same things and had the same world view this would be evolutionarily a disadvantage. Just brain chemistry changes alone could account for a lot of decisions. At a crude level it makes more sense to be sex and love obsessed in 20s when the chance of having a good sperm, eggs and pregnancy is much higher.

Elder members of the group help genetic survival by providing wisdom, knowledge of a different kind than younger people (I don't believe "older people know better") but the blends of knowledge are great for survival.

The assumption that we are purely rational agents making informed choices is clearly false in general, and I think the opposite is true, in general.

And this doesn't even tough on the extra information you would have processed over 20 years or even the freakingly high speed of change of the world around us. Would you choose to learn about Machine Learning / Neural Nets in 2000? Or coding in 1980? Well you could if it is a passion, but it didn't look as promising as now right? So data changes.

It's not just about missing out on what you want: it's also achieving it and wondering, "is that all there is?"

There are too many unknowns and uncertainties to consider anyone's life choices a failure. Don't fall victim to the illusion of control.

I think you're also falling a bit for one of the common fallacies people who have midlife crises have, the idea that there's something wrong with changing the direction of your life at 40, that it somehow means you've failed.

Having helped a couple of people going through that sort of phase, a pretty useful tool I found was to have them think about how much the world has changed in even just 20 years. So, given that, it isn't really that big of a deal that at 40 you might want to do something completely different from when you were 20, simply because your current life is almost entirely different to what it was 20 years ago.

We're long past the times when several generations of people would live and die doing the same thing without seeing any meaningful change in lifestyle and so it isn't that big of a deal if that also reflects in our own life choices.

I'm in my 40s and haven't had one, but I've also never really figured out what I want my life to be like. In truth the question was always more what do I want to do right now? What you want life to be like will continually change, and to me, it seems like those who don't accept that end up disappointed.

I'm currently in a transition period, seeing if changing course from my present occupation is possible. I did the same in my 20s and 30s without difficulty, though it gets harder as you age. If I can good, but if I can't, then it's still ok. Make the best of what's available and enjoy what you have.

Life is a long series of decisions and then you're dead. What you do doesn't really matter, even if the pressing weight of it right now says otherwise. Make life choices that won't pigeonhole you and be open to opportunities you may not expect.

You could be on the right course but still unsatisfied with your achievements. This is probably pretty common.