The issue isn't when he's open, it's when he has to create his own shot which is a key factor for players trying to become NBA stars. It's not as critical as it used to be because of the changes in the rules and offensive schematics. But, it's still a critical part of becoming a star versus a good team player.
He's got super range, but since he's a typical drive if he goes to his right and pull up jumper if he goes to his left, his mechanics are critical because with his mechanics it's easier for the defender to get a piece of the ball. And thus if the defender protects against him driving to the right he can make it difficult for him to score. This is what we saw out of the Kentucky game with Ball. The Kentucky defense was able to take away him going to his right and it really gave him problems.
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