[itsankur]

So if it isn't drive, than that really only leaves: - genetics - coaching/enviornment?

Basically, you are born with the required genetics + surrounded with the right coaching from a very early age or you won't get into the NBA right?

Are there other factors you think contribute? What percentage weight would you put on each factor if you had to guess.

I think you're likely correct here. There's definitely exceptions to this, but those exceptions fit into the 99.9% figure you have here.