From wikipedia
http://en.wikipedia.org/wiki/Kirk_Ferentz
Pro football opportunities
Many major college and NFL teams have considered Ferentz as a candidate for their head coaching jobs. However, Ferentz has publicly declined any interest in other coaching positions, opting to stay at Iowa. On November 23, 2004, Ferentz and Iowa athletics director Bob Bowlsby agreed to a new contract extension that keeps Ferentz at Iowa until 2012.[1]
On January 2, 2006 the head coaches of five NFL teams, Green Bay, St. Louis, Houston, New Orleans, and Minnesota, were fired. There was renewed speculation that Ferentz would be offered a head coaching job with one of those professional franchises. But such speculation was soon put to rest when Ferentz stated that he was still happy with his job at Iowa, and that he had no plans to leave.[2]
On June 2, 2006, Ferentz became the highest paid coach in the Big Ten and third highest in college football when he was given a restructured contract that boosted his annual salary to $2.7 million.[3]
Following the 2006 NFL season, rumors circulated that Ferentz may have been in consideration for the Pittsburgh Steelers' head coaching job after Bill Cowher stepped down. However, before Cowher's departure, Ferentz was asked about his possible interest in the position, and stated: “I know that staff pretty well and they’ve got some good guys in that building. My guess is that's where they would go. But I’m not interested, and I doubt they are, either. I’ve got a great job right here.”[citation needed] The Steelers job eventually went to Mike Tomlin.
In 2008, Ferentz was again rumored to be a candidate for an NFL head coaching job, particularly as successor to Romeo Crennel for the Cleveland Browns.[4]
Plus he earns $3.2 million a year for a job much less strenuous than an NFL gig.