I'm not sure how best to answer this question. On the one hand, I'm studying for a PhD in a competitive field. If I'm not in the top five or ten in the country there's a good chance I won't get a job at the end of it, and I've had to consistently be in the top five in my class at every level of education to get where I am now. On the other hand, what I'm studying is philosophy. If you're working hard at philosophy then you're doing it wrong.
Thinking back to secondary (or "high") school and college, generally I worked as hard as I felt I needed to in order to achieve my next goal. Being the best, or being above average, was never important because I wasn't generally in direct competition with my classmates. Occasionally I bet against the guy sitting next to me in economics over which one of us would get the highest grade on the homework, but the grade itself wasn't the motivating factor.
Incidentally, earlier this week I was going through the training to be a tutor for undergrads and they brought up an interesting point regarding this be-the-best stuff. Apparently in a lot of countries, particularly in East Asia, there is a lot of emphasis on competing against your classmates. We were specifically instructed that as tutors it's our job to explain that that's not the way education is supposed to work here. You're not supposed to be better than everyone around you - you're supposed to work together to further each other's education. Discuss the homework in groups and help each other through it. It's better for everyone.
Edit: I've just noticed that my post looks contradictory - I've said that I've had to be in the top five in my class to get where I am, and then gone on to say that I was never in competition with my classmates. What I mean is that, as it happens, my classmates were at a level such that getting into a masters/PhD course required being in the top five, but even if they'd been super-geniuses and I was the worst in my class I would still have gotten in with the grades I actually achieved.