1) Losing the left wrist cock too early.
2) Throwing the right hand into the ball and losing the essential right wrist bend in the process - related to 1) above.
3) Starting down too fast and running out of clubhead speed prior to impact.
4) Incorrect ball placement at set up.
5) Casting from the top.
6) Trying to hit up on the ball by scooping.
7) Incorrect weight distribution - associated with, or not, 6) above
8) Reverse pivot on backswing - associated directly, or indirectly, with all the above.
9) Sliding forward on the downswing and changing the low point.
10)Hitting at the ball rather than swinging through it.
Thats got the ball rolling.