In college football the ultimate goal of a team is to win the national championship, but in order to achieve that goal the team must first win their respective conference. Some teams are built to contend for the conference championship year in and year out, but just don't have the coaching to get over the hump.
Several teams have the potential to make the conference championship, but their coaches just can't coach them to the trophy. In college football it is a difficult decision to let your head coach go especially with all the loyalty involved and several coaches having long tenures with their schools, but if they can't get you to the big game and further, something has to change. Great records are nice, but they don't always equate to conference and national championships.