The Bills hired Ryan after Doug Marrone opted out of his contract following the 2014 season.
It seemed like a strong partnership at the time since the Bills had just finished 9-7 under Marrone, their first winning year since 2004, and were led by a young defense that finished fourth in yards and points allowed. Ryan is a defensive specialist who guided the New York Jets to two AFC title games in 2009 and 2010.
But things haven't worked out. The Bills went 8-8 in Ryan's first season with the team and have been inconsistent this season.
Ryan is a charismatic coach, but it did not translate to wins for the Bills.