It is fundamental to understand the coming ball’s characteristics right when it leaves your opponent’s racquet. Less expert players often get these characteristics only when the ball has already passed the net and bounced. At that moment it will be too late and technical and tactic decisions will be affected by the little time available to get ready for the ball’s execution (stiffness, loss of balance and of the ball…).
Remember that when you play from the baseline there are two ball’s movements: one goes from your opponent’s racquet to the bounce and another one that goes from the bounce to your racquet. Both offer you some crucial clues on how to prepare for the next shot.