The mental side is a big part of it. But there are also some real skills Nika has yet to show. I realize this is an unfair comparison, but think about all the ways Paige or Azzi (or Christyn) have of finishing at the rim -- the floats, finger rolls, baby hooks, reverses, pop-ups, side-arms, all the ways they know to use their bodies to seal off a defender, to generate contact, to force a foul. Nika has not demonstrated any of this. She doesn't have to develop a full arsenal. But there's definitely skills to work on, and the good news is that practicing skills like these is the main way to develop the mental side.