Every golfer knows that developing a smooth, consistent swing is essential to improving one's game.
From the top of the backswing, behind the head, through the accelerating down stroke, through the ball, and continuing up on the follow through, the club head should never leave that desired plane. Quite a number of lower back muscles put a twist into the torso and then unwind it. Other muscles direct the paths of the shoulders, others yet, the elbows. More yet define the position and motion of the wrists. Then, based on all those operating perfectly, the flexing and recoiling of the hands and wrists must be precisely controlled.