I think it has to do with luck as much as anything. Not luck in actual playing but luck in how you learn, from who you learn and being able to find a perfect mesh of eyes, hand, stance, right shaft, right cue, right table, right teacher to be able to line things up properly to get to the highest level. At the beginning I mean, it's like being on a track from the start, till you hit your peak instead of getting into a half broken car trying to drive though Boston roads.
We always wonder if the best at anything are really the best ANYONE can be at it. What if there is some kid who just never shot a basketball but has inside the potential to beat Jordan and LeBron at the game if he started to play? Need some luck to go along with dedication and mental toughness to be a top at anything I think.