This is why the Flyers emphasize work ethic and love of the game, at 19-21 years old there are a lot of distractions, especially in the off season (I can spend the day in the gym and skating laps and sprints, with a hot girl, with friends drinking beer, which do I choose?).
He’s a kid that’s played over there (in Sweden) and played OK and done those things, but he never really invested the time in the offseason — to get stronger to put on weight to do the things that would give him a chance to play over here. I think, finally, he did. He’s a kid that has always been blessed with good skating ability, he can defend, he can move pucks. But he was one of those guys you always (thought) there’s another level to him.
My suspicion is that this is true for a lot of prospects, it' s not that they're "lazy," it's just that they're not "ice rats". As JJ Watt pointed out, when he's 35 he'll have lots of time to drink beers with his buddies, but right now it's all business in a career with a limited timeline. Some kids get this early, some later, some never. And that may partially explain why some prospects mature faster than others.