When I was growing up, I'd look at musicians who would seemingly have everything going for them and be completely blown away at how many of them would walk away from it or somehow self-sabotage things.
Why would somebody do this?
It's the same reason a guy walks away from dating a supermodel -- the situation on the inside isn't what it appears to be on the outside.
We think we know what we want, but until we actually experience it, we can't say for sure. Being a musician, or surgeon, or pilot, or attorney, or astronaut is pretty doable -- if you're willing to do the work.
But none of these things are like we think they are when looking at them from the outside. And this is why there is such a big difference in the amount of people who say they'd like these careers as opposed to the people who actually have them.
Most people figure out something isn't a match before they get to the final destination. Some people don't, which is why they walk away. Beyond that, people change. What worked for you last week might not work for you today.
If something isn't working, you have options. Life isn't always easy, but there can be ease.