A correctly positioned ball is necessary for a square contact at impact. The location of the golf ball affects both your shoulder
alignment and the steepness of your swing. If the ball is too far forward in your stance (towards your left foot), your chest must turn toward the target so that you can sole your club head behind
the ball. This “opens” your shoulders and because the club swings where the shoulders point, you will have a slicer´s swing path—steep and outside-to-in.
If you locate the ball too far back in your stance (towards your
right foot) than your chest must point to the right of the target, “closing” your shoulders and creating a flat, inside-to-out swing path. That´s not you want either.