Why? Did you not like his tape?
Rosen is a very nice passer. Give him a clean pocket and he makes all the throws with solid accuracy, anticipation, and timing. But there's more to quarterbacking a team than throwing the ball (which, incidentally, is why I hate using volume stats to determine how good a QB is -- sometimes the right move is checking into a run play). That's where I get concerned, and it's not the fluff about his hobbies or unsubstantiated rumors about supposedly rubbing coaches the wrong way. I don't really care about all of that. These are grown men and professionals; they'll deal with whatever.
No, the same concerns I've had in college have carried over to the pros. People like to point to how bad his OL was (and it wasn't great), but I can't tell you how many times he failed to see a clear blitz or pressure coming. He rarely seemed to slide protections or go to his hot read. Maybe that can be taught. But my problem is that he seems bright enough, and he gets all that in film study / whiteboard work, as you can see in any number of interviews or media workout sessions. The mental clock just moves too slowly on the field, and it seems to get worse the more the pressure gets turned up, just like we saw with Goff in the Super Bowl. Obviously no quarterback likes to have pressure in his face, but I came away from Rosen's college and pro games with a strong sense of that I don't have confidence in his abilities to elevate a team and push for a win by himself.
Put enough pieces around Rosen, and I think he can win. He can make the playoffs. He may even make it to a conference championship a couple times in his career. I do not believe, however, that he has the drive or determination to take a team to the next level. He'll struggle with quick processing and get shut down. Now, he's relatively smart, so he'll start to dissect what happened, but that's what will do him in because I don't think he's got the right perspective or ingredients. The problem I have with Rosen is that I'm willing to bet almost anything that he will find ways to explain all the factors that led to his performance, and he'll work on those various outside contingencies, and he'll think it's going to make a difference, instead of holding himself to a higher standard and striving to be better.
Maybe I'm wrong, but nothing we saw in his rookie season, which featured some of the worst stats of any QB in the entire NFL, gives me any hope for his future career trajectory.
