Some coaches just get in their head that certain kids are the stars, when in fact they aren't and reality is evident to all parties involved but the coach.
And this isn't some veiled rant about my kid as he takes after his mother and is slow, lacks spatial awareness and has terrible hand-eye coordination.
I'm also not talking about the coach playing his own kid as QB or point guard who is a dunce and a fat tub-o-lard. It occasionally happens in situations when the coaches don't have kids on the team.
Better coaches more quickly assess and re-deploy talent, at least from what I've seen. Rees, and to an extent Kelly, seemed to make their mind up on guys and once they did it was all over.