Kind of a tough angle from which to analyze. But the first thing that jumps out at me is the pause at the top of the knee lift. Maybe he’s been taught the ol’ balance point drill? Would prefer to see continuous, fluid movement with no pauses.
It also looks like he pulls his glove back after extending it forward. This often leads to early shoulder rotation and can affect both performance and health. Try to get him to turn the glove over and stabilize it out front while bringing his body towards the glove.