Path of the racket, angle of the racket and speed of the racket are the 3 indisputable factors that affect the flight of the ball and are the 3 concepts to understand and look for in a player’s technique.
If missing in the net one needs to have a steeper low to high swing path if hitting topspin. For more of a flatter shot a player needs to have a more linear swing path, and not so steep.
Racket angle – for topspin a racket needs to be closed swinging forward and for under spin the racket angle needs to be open.
The faster the speed of the racket the more spin and speed will be imparted on the ball. In todays game fast racket speed is absolutely essential.