I was always taking things apart as a kid (usually breaking them), started with computers my jr year in high school, and won the U of L ACM programming contest that year. I have always loved programming. I billed Ford 300 hours one month when I was 25 and working as a contractor, and that was time actually working. But even though I have always worked long hours, it was always more like play than work and I never felt burned out.
I ran a web business from age 38-45 with a co-founder and we worked our asses off 7 days a week, 10-12 hours a day. Still, I never got burned out, rarely took any time off (single, no kids). He bought me out after 7 years because I wanted to do a backup thing and he wanted to expand the web business. Made a good hunk of cash from that over the 5 year buyout.
I wrote a Prime minicomputer emulator and licensed it for around 12 years. One customer paid for my rather frugal (by choice, not necessity) lifestyle.
At 49 I released the first version of HashBackup and have continued that the last 12 years. I'm not taking money for it because so far, I haven't needed it, and dealing with money is a pain.
My personal life was practically non-existent in my 20's because I worked so much (loved it too), but looking back I'm glad that I sacrified personal life for career. It has always given me the option of turning down work I wasn't interested in and leaving jobs I was no longer interested in. I never had to take a job for money. Having a spouse and kids obviously makes that a lot harder.
I feel like there are always trade-offs in life. I have a $22/mo cell plan from puretalkusa.com, am grandfathered in on the "Everyday Low Price" internet plan from Time Warner (now Spectrum) that originally was a whopping 3Mbit down/1Mbit up for $15/mo, but over time is now 20Mbit down/1.2Mbit up for $27/mo. I was recently rear-ended and had to buy a car, but bought a 2018 Acura RDX with 30K miles for $26K instead of a new one for $46K. I also bought a completely rebuilt 1918 mahogany Steinway B a couple of years ago, so I'm not shy about spending money, but it's also fun to beat corporations at their pricing games. I buy clothes at Goodwill most of the time, because I hate shopping and if I buy something at GW I don't like, I just give it back and don't feel bad that I spent $75 on a shirt that I don't like when I get home. I buy all my Macs and phones on eBay for usually half price.
In a lot of cases, people have choices in life, but they sometimes don't spend much time thinking about how their choices affect their life. I see people in brand new trucks that cost $60K+ and it makes me wonder why anyone would do that.
If a person wastes money over a lifetime, I think they will have a lot more financial struggles and maybe never have the option to retire early. I've always been frugal because having money gives me choices and options.
A key thing to being happy in retirement IMO is to take care of yourself and have at least a few things you are passionate about, whether it's side projects, music, sports, poker night, or whatever. I try to make the most of each day, even if I'm not getting paid for it.