Mebron (when he plays "all about ME" basketball) is the way he is because he doesn't have a coach who's taught him how a real team works (and yes, maybe its partially because he never had a coach who made him play team ball in college). Perhaps he is a coach killer because the owners cowtow to him and let him get away with thinking the game is played with the ball in his hands.
But, I think the REAL problem is that he doesn't have a coach or play in a system where the point guard gets HIM the ball down low where he can use more of his strengths late in the game. He could kick the ball out to others if double teamed (he's a good passer) or he can take someone one on one. He could even do pick and role. But, he can't hold the ball all of the 24 second clock. Even Pierce loses his effectiveness when he falls into that trap (as does Kobe).
Letting the PG doe their job also means the point guard can't get Bosh the ball or Wade the ball in good situations.
I blame Lebron's problems on coaching more than anything. Doc, Phil, Sloan, Pop, Avery, and coaches like that would NEVER let this go on so long.