The one that bothers me the most is when I hear someone say they need to get under the ball

The obvious one you hear is “You picked your head up”. There is probably one person in every foursome that says that for every bad shot. Yes you can definitely have improper head movement, but it is not root problem for every bad shot.

The one that bothers me the most is when I hear someone say they need to get under the ball. Getting under the ball gives you a visual of trying to lift the ball off of the ground. When in reality, when the ball is on the ground, we want to swing down and through the ball at impact.

The goal is to make ball then turf contact, not to try and get under it and lift. If you try to get under it and lift you are going to get a lot of fat shots and also thin shots.