As a parent I am very conscious of actually not pushing the idea that you got to be best. I think that easily causes the opposite. If you are preoccupied with being the best you will never dear try something you are not good at. How can you become good at something if you don't try it out?
But I do try to emphasize that to become good at something you have to practice. I tell my kids when they fail, that that is good, because it means you are learning. If they don't make mistakes it means they aren't pushing themselves enough.
Also my philosophy is that it is better to be average at something which pays well and there is a lot of demand for, than to be a super talent at something you can't make money on and nobody is interested in.
I think that is very important, because I see so many people give up on hard subjects like math and physics because they can do better at easier subjects and they are so preoccupied with high grade averages. I say, screw that and instead be average at something useful.
You should of course try to follow you heart but if study something you really enjoy but never get a job afterwards in a related field, you will reap a lot of misery for years just so you could enjoy a couple of years in college.