Ego. I'm no Michigan fan at all, but who wouldn't want to go to there Alma Mater and resurrect a program that has been struggling and bring it back to the top. I think Les Miles is a great coach. You don't win in the SEC for that long by pure luck. I don't know how much money Michigan could offer. I'm sure they owe Rich Rod for another year, so who knows how much they can put up. Money and ego always seems the trend. So, to answer your question why would he leave. I think he would just so he could say to the world " look how great i am". I think alot of coaches have done it in the past and there looks to more of it on the way.
P.S. Heard on the radio this morning that Rich Rod is being sued by the couple that bought his house from him here in WV. There apparently was a major leak causing damages to the home. The couple said they were never notified of any leaks or water damage by Rich when they purchased the home. Also, the couple said there was also a boat in the agreement. Rich rods lawyer said the house was sold "as is" and that there never was an agreement about the boat.
I wonder if Glenville would consider hiring Rich Rod back?
LOL. Maybe. But im a Glenville Alum, so i hope not.