If the driver is too far back in the stance, it can cause a number of issues. It can lead to an inaccurate shot as the clubface will be open at impact, resulting in slices or hooks. Additionally, it may also reduce power and distance off the tee due to a decrease in clubhead speed. Finally, it could also cause an imbalance during the swing which could result in poor contact with the ball and further inaccuracies. To ensure optimal performance from your driver, make sure that you have positioned yourself correctly relative to where you want your ball to go.