25. Tony Sparano
Years active: 2008-2011
Win-Loss record: 29-31
Team(s) coached: Miami Dolphins
It's hard to call Tony Sparano a terrible coach, as he engineered one of the greatest turnarounds in NFL history in his first season with the Miami Dolphins, but the fact that he failed to make these changes stick is telling. After Cam Cameron had led the Dolphins to a 1-15 record in his only season with the team, Sparano righted the ship and took them to a 11-5 record the following year with most of the press gravitating toward his "Wildcat" offense. It was the franchise's first playoff appearance in seven seasons, and remains their only appearance since. However, Sparano failed to keep this momentum going, and the team had back-to-back 7-9 seasons before he was fired near the end of his fourth year.
Now an assistant head coach with the Raiders, Sparano has a better shot than most to end up with another head coaching gig someday, but we still wouldn't bet on it.