4. Matt Campbell
Remember after the 2020 season when Matt Campbell was the up-and-coming superstar head coach? Well, his loyalty to Iowa State cost him a lot of money because sometimes it's best to strike while the iron is hot. Campbell could have taken quite a few jobs after that 9-3 season that had the Cyclones finish at No. 10 in the College Football Playoff rankings.
Since that year, Campbell has gone 7-6, 4-6, and 7-6. What was a rising star in the industry has since crashed back down to earth. Michigan would be buying low on Campbell and it still may not get its money's worth.