Not OP, but I was also replying and had thoughts along a similar vein.
I'm 44 and have had countless hobbies over my adolescent and adult lives. Some I've taken up multiple times, some I've visited multiple variations on a core idea (e.g. aquariums/planted tanks/dwarf shrimp tanks). I've learned (and subseqeuntly forgotten) a tremendous amount, and spent an unholy amount of money. Most things have not stayed with me.
Miniature painting is one thing that I think might last me the rest of my life.
I think it boils down to a few factors:
- miniatures aren't alive; I don't need to care for them, so the worst that can happen is I break or scratch something. This keeps my anxiety/concern/guilt largely out of the equation.
- the feedback cycles are fairly short; I know almost immediately if a paint stroke was good or bad, if my brush is too wet or too dry, etc. A single project is normally just a couple of hours, and then it's done and I can view it as a completed whole.
- the product occupies little space and it's trivial to keep around and compare to work done before and after and see progression and evolution over time. Also, if you're prone to collecting things, just keeping the product on the shelf next to other things becomes an ongoing source of reward.
- if I absolutely fubar something, I can buy or print a new mini for a couple bucks or throw it in some Simple Green overnight and brush the old paint off. Most of the time I can just paint over the issue.
- paint, brushes, a wet palette, minis, airbrush, etc all add up, but you can have an amazing setup for under a thousand bucks, and you can transcend the realm of mortals for $2K. The ongoing costs after that are manageable unless you're into Warhammer. You can get started and do some really fun and cool things with a $50 starter kit.
So there's some higher-dimension graph with effort, frustration, reward, feedback latency, etc, and for me at least painting miniatures tends to sit in a happy area.