"Drive" by Dan Pink sort of talks about that. Your purpose should be something that you provide, not external factors, like grades and fears from what comes from them.
I dropped out of school, got a job that was supposed to teach me something. It turned into answering the phone, but I used that time and title to land a Jr. software dev position and within just a few months I was being assigned solo projects and completing them ahead of schedule because I actually enjoyed learning the material outside of a structured environment.
I'm not a genius. I'd bet I'm not even that special. I think many people are just too conditioned to follow the wide beaten path, that even when they see a more appealing path they are scared to take it, and no one is actually encouraging them to take that path.
Enter the real world, and guess what? Critical thinking skills and a tenacity to solve real problems are in tremendously short supply. You've got high-GPA graduates galore who can't tie their own bloody shoes. Motivation is everything.