The ability to maintain our spine angle or rather keep our inclination to the ground is important so we can strike the ground in the same place every time.

If the pelvis moves closer to the ball on the downswing and we extend our spine early, the tendancy is for the path to move too much to the right causing a push and a hook.

You can practice this drill at home by making sure your butt stays against a wall during the backswing and downswing.