23. Rick Pitino
You don’t have to be a bad coach to be ineffective. Pitino became a massive hero in New England with his college coaching success. He took Boston University and Providence far in the NCAA tournament. The Boston Celtics decided that he was perfect to revive their fortune.

However, he struggled under the pressure of the major league and posted three losing seasons. His tenure saw him leave a 192-220 record behind. Finally, he got sick of the negativity around him and quit. Insanely, this meant walking away from a $20 million contract with six years left.