But when people choose to do something, they can change and choose to do something else. If they don't have the necessary skill set or physical limitations... well, there is no changing that. Take Ulis as an example- no matter what he chooses to do, he is not an NBA player. He can't magically grow five inches. Knight CAN shoot, dribble, pass, even play some defense. He just chooses not to pass instead of taking bad shots. That CAN change.
EDIT: For the record, I don't think Knight will change, but he certainly could if he wanted to.