It seems that no matter where he coaches, he hardly ever gets credit for the wins and takes a lot of blame for losses. The man's coaching record speaks for itself. In Atlanta, he improved his team's record for five consecutive seasons despite having a team consisting mostly of isolation scorers. With the Knicks, he's had a 32-10 record in the regular season despite a plethora of injuries and roster changes.
The only knock on him is that his teams don't perform in the playoffs but I don't think that's a very fair criticism. His teams in Atlanta were poorly put together and were simply not as good as most of the teams they lost to. Last year with the Knicks he went up against the Heat and had several injuries to key players, so it's hard to blame him for that series.
He's an excellent defensive coach, he gets everyone to play hard and holds them accountable for their mistakes, and it seems like his players respect him. Let's give the man his due.