Oh so many reasons he's a bust.
1. He was a physical beast in junior, but once he got to the NHL he was too small and didn't play with enough tenacity to really be any sort of physical presence game in and game out.
2. His shot while very hard is horribly inaccurate. It doesn't matter how hard you can shoot the puck if you don't hit the net. A handful of times he'd just blow one by a goalie and everyone would be like "WOW what a shot he has" but most of the times he'd just shoot it wide or right into a goalies bread basket.
3. To go along with #2, even if his shot was accurate, he never knew how to get open to use it. I've never seen a player who so frequently is facing the wrong way on the ice. Oiler fans for years accused basically everyone on the team of "looking off" Yakupov and not passing him the puck. It's because he was never actually in a position to shoot the puck.
4. He's a quick player, but not a fast player. You'd never see Yakupov break away from a defender or blow by someone. Just doesn't have the kind of speed you'd expect from a small scoring winger.
5. Overrated stick handling ability. He has a tendency to over handle the puck. Not in the sense that he'd try one move to many, but in the sense that he seems to have difficulty skating with the puck on his stick without losing it. Nothing is ever smooth for Yak.
6. He passes the puck too hard. Seriously lol. Yak never seemed to realize that he might need to take some power off his passes. He'd whip it around and guys just wouldn't be ready for it or it would end up 3 feet off the ice.
7. Zero hockey sense. Like... none. In the o-zone or the d-zone, Yak has no clue what to do out there. He just doesn't process the game at a fast enough level. Ends up in no mans land all the time.
I list all of these things and I realize it comes across like I hate the player. I truly don't. I love Yakupov. He has a wonderful personality, and there was never a player I'd feel better for when he scored. It was just so exciting when he'd bury the puck. You could really sense his excitement and exuberance through the television.
But... he's just not good enough to play hockey at a competent level in the NHL. Unfortunately for him he had a lot of tools that let him destroy junior, but not one of those skills was quite elite enough to make up for all of his other shortcomings.
Maybe he'll be able to head off to the KHL and play there for a few years and find a different style or develop his ability further. I'd love to see a successful Yakupov in the NHL.