Back on topic, I think, there is coaching and there is execution within a real live game.
As most of us, including me, are not privy to watching the coaching sessions, there is no way for us to know if the issue is coaching or lack of execution of a player in a real live game situation.
Yes, we can see patterns on game day - but we don't know if said coach told player to do something and they did something different or vice versa.
But I am sure a coach does not tell a receiver - thou must drop the pass X times during the game, or tells an offensive lineman to hold or not block.