The driver requires an upward hit and to do that, the spine needs to lean away from the target. Because the ball is positioned forward and our right hand is lower than our left hand at address (for a right-handed player), we should naturally have some spine tilt in place before the swing starts.
But what many amateurs do incorrectly is begin their downswing with their upper body, which causes the spine to tilt in the other direction, leaning forwards. This makes the angle of attack too steep and results in weak drives that will often miss right of target.
Your goal should actually be to increase the amount of spine tilt away from the target during the downswing by shifting the hips correctly.
Moving the hips towards the target to start the downswing increases the spine tile and helps attack the ball from the inside for a powerful draw rather than a weak slice.