"In other forms of Kung Fu or in Karate and other martial arts, you tend to use force all the time and it limits your development of control. In Wing Chun knowing the right moment to use force is critical."
"Frankly speaking, Wing Chun is not for drama, it is for efficiency."
"In combat, those who have a lot of experience will deliberately make you waste your energy until you have not m uch left, and then they can take their time to hit you back. So the first lesson is: conserve your energy."
From Yip Chun, Wing Chun Martial Arts Principles & Techniques.