Coyle and Colvin describe dozens of experiments fleshing out this process. This research takes some of the magic out of great achievement. But it underlines a fact that is often neglected. Public discussion is smitten by genetics and what we’re “hard-wired” to do. And it’s true that genes place a leash on our capacities. But the brain is also phenomenally plastic. We construct ourselves through behavior. As Coyle observes, it’s not who you are, it’s what you do.
So my adaption to Brook's comment would be , it's not who you are, it's what you make of who you are.