If he wins a title with Ohio State and keeps the competitive for the title after that they will treat him like a king. He has complete control over his roster and his team at the NCAA level. Only bad NFL teams give their coaches that and I think he's smart enough to know that.
He may well want to jump to the NFL, but to say he has no incentive to stay at Ohio State after winning a championship is just silly.
Also, this:
Works for Nick Saban