His shot hasn’t translated to the NBA yet. He’s a rhythm shooter and has been stuck in a numbers game in Memphis who were top heavy with bigs.
He’s also been injured and I don’t think he’s fully recovered from back surgery. I don’t think he’s as bad as Roy seems to think, he was just in the wrong situation.
His ceiling is a role player and always has been. A 2nd rate Gallinari who can shoot and pass, mediocre rebounding and defense. Memphis plays a speed game with Ja and he’s more a half court player.