I've seen that at play, and it can be a very significant effect. The clearest instance from my personal experience was in self-studying mathematics. I began my regimen of study literally the day after finishing my CS degree. I'd had a 'repetitive strain injury' related to computer usage for years at that point, and had figured I would never be able to work as a programmer again (did a brief stint as a teenager). I needed to find something else and had been searching for a long time without luck—but now I had something: I'd just earn money doing mathematics somehow!
It was grueling to work on at that time because it seemed like my last option for being able to do something that used my creative/technical abilities as a career (I was working at a grocery store then to put things in perspective)—and I just had no idea if I was going to be good enough with math for it to be a realistic possibility. So it was nerve-wracking anytime I attempted something that would test my ability.
Several years later, after figuring out the computer use issues—I didn't need mathematics anymore. But I'd spent a lot of time learning, gaining proficiency, and developing interests in various areas; so at some point I got back into studying again. The difference is night and day—I'm far more productive, and it's just, by comparison to before, no big deal.
Highly recommended if you can settle it with yourself that you're okay with things however they turn out in relation to some hobby/skill/whatever.