No matter how much you practiced, you would never be as good a swimmer as Michael Phelps or as good a basketball player as Michael Jordan. You would never be as quick a thinker as Stephen Hawking. There are fundamental biological differences that orient people toward being naturally better at some things than others that if given equal practice, the person with the natural gifts will excel more in. That isn't a bad thing, it is the crux of humanity to have different people of different talents that should motivate people to rely and build together.