He's homegrown for starters, that's a key factor I expect.
I don't think he's destined to fail - he might, he might not. He's got a chance to step up to the plate and if he does well, he'll get games.
We need two players for most positions, there's be injuries, suspensions, cup games etc. Surely if any player wants to make the grade at a top club, they have to move there and make their case.
I know he's not Pogba etc, but I don't see this move as a career downer for him.