The swing plane station is to help direct the routing of the golf club in the golf swing. A key component to swinging in the club plane is how your body is moving, specifically from your hip joints up to your pelvis and torso.
It is important to create the right movement and right tilt within the backswing. Rotate your spine from a bent-over position to a bent sideways position. This will have a direct effect on the swing plane and will help you achieve a more on-plane swing.
Putting a swing on-plane and staying in posture within the swing will help you create consistent shots and better contact, leading to lower scores.