19. Mike Shanahan
The story of Robert Griffin III is one of the most tragic quarterback tales of them all. The former Baylor star had a magnificent rookie season and even made the Pro Bowl. But he never played in it because of a devastating injury that effectively compromised his entire career. Furthermore, Shanahan had significant responsibility for Griffin’s injury.

Griffin tweaked his knee in week 14 in 2013 but came back for the postseason. When he felt it again, the Offensive Rookie of the Year should have left the field. But Shanahan didn’t protect his rookie QB and kept him in. Then Griffin tore his ACL and LCL and totally wrecked his future as a starter. His form never recovered and he ended up bouncing around the league as a backup.