I started investing myself at 31 years old in 2007. A thousand euros from the housing loan was left unused, so I immediately went into it with 100% leverage 
I knew nothing about it, I just bought a few shares. I only added more if I got more money, i.e., from holiday pay and tax refunds. No strategy or knowledge whatsoever. I just watched the stock price. I traded them in every direction. I guess I was waiting for something to, say, a thousandfold.
I also invested in OP’s expensive pension fund, until a couple of years later they announced they were raising the age at which you could withdraw money from it, I think by a couple of years 
I tried to close the fund, but the notification was that it wouldn’t work unless I quit my job, divorced my wife, or died.
I stopped transferring money there. I’m not even an OP customer anymore, that fund lives its own life there. I managed to accumulate about 2k there.
During the Corona period, my portfolio approximately doubled. Suddenly, the portfolio was worth about 7000 and I thought I could start researching this more. I emptied the portfolio and researched more carefully what companies I started putting in there (I know, taxes. It tells of my understanding at that moment).
I also started index investing. I hadn’t known about this before, not even the bank advised me, because they wanted to sell a more expensive fund; it’s easy to trick the ignorant.
Now my portfolio, including funds, is worth 16k. I don’t know the total historical return. As a Finnish investor, after the reset, it started to stagnate, and the return on OST is slightly above zero (currently YTD 23%, stay there) 
I wish I had known about index funds. After buying the apartment, my wife fell seriously ill and had to go on disability pension. Being young, she hadn’t accumulated much pension or work history due to her studies, so her pension isn’t very substantial (she worked for a while at an accounting firm, and the aging owner had started discussing whether my wife would like to buy it from him; our lives could be very different now. For better or worse, one never knows).
I myself was a factory worker (still am), so not much money was left over, and due to the buying costs of direct stocks, it’s not worth doing with small sums; I could have accumulated in index funds.
However, it doesn’t bother me. That’s just how it has gone now.
My life has been very challenging mentally in every way. I have also kept myself busy so that I wouldn’t have to deal with things.
I have “lived” as one should say. In my opinion, too much glamour has been put into that phrase. That living, at least in my case, involved many foolish acts, and alcohol has also become very familiar. I guess you could call it binge drinking, because I have still managed to keep my daily life running.
Things could have been left undone, but do I regret anything? No, because it doesn’t matter. I am the sum of my life, and history cannot be changed.
At 43, I then suffered a severe burnout. Things had to be dealt with. They eventually do.
I went to occupational health, was on sick leave for a few weeks, and got a referral for psychotherapy and an ADHD diagnosis at the same time.
I had already started working on myself earlier; I had also received a moderate depression diagnosis in 2008 and recovered from it (I doubt the entire diagnosis).
I have been anxious perhaps 80% of my life. Nowadays, perhaps 10%. The change is enormous.
I have never had dreams of getting rich, wealth, power, or life in general. I haven’t been able to see my future; there have been periods when I questioned all of existence and wished for my death.
Now I look forward to the future. I don’t invest for wealth; that comes as a bonus if it comes. The feeling of accomplishment is what I seek with it.
I have learned to think about things through need, not desire (which, by the way, has had a big impact on my mind and finances; yes, money does bring happiness too) 
A large amount of material possessions only causes extra stress.
I believe in balance and strive to keep my life mediocre. I haven’t succeeded in that yet. And I don’t know if I ever will. I can’t stay still, and that’s something I’ve also had to accept. I just no longer waste energy on anything harmful, but on things I’m interested in and enjoy.
My only fear now is that I won’t have time to learn and see enough. The world is full of amazing things 
It got out of hand. The intention was just to participate in a discussion about why to invest. I just thought I’d provide a little background. I don’t even know if it belongs here 