I'll repost what I posted in another thread:
Football Outsiders: College stats don't lie
The single best predictor of success percentage is completion percentage. Rosier's completion percentage last year was 54%. That is not just categorically bad, it is quite literally nearly dead last in the ACC.
2017 ACC College Football Individual Statistics Leaders for Passing - ESPN
If Rosier was dead last in any other metric like passer efficiency, QBR, or TD/INT ratio I'd be willing to consider the possibility that Rosier just had a fluke bad year and had the potential to bounce back and lead Miami to the ACC Championship game again next season. The fact that he was so unbelievably bad in the one metric that is the most strongly associated with being a "good qb" (completion percentage) leads me to believe that Rosier instead had a fluke good year (in terms of wins and TDs) that is unlikely to be replicated next year. Again, I point you to the fact that we were two miracle catches away from being 8-5. A stat like total number of TDs has a lot to do with the number of scoring opportunities per game, and Miami gave Rosier a TON of chances as the D was averaging 4 turnovers a game. There is a far, far greater chance that Rosier will have a a bad year in 2018 than it is likely that he has a "breakout season." Don't get it twisted, I have nothing against the kid and kudos to him for hanging in there last year. Unfortunately for him (and us as Hurricanes fans) the stats don't lie.