"Don't quit because you are frustrated. Find a different aspect of the art, or your motion, to focus on and develop."
This especially applies to Wing Chun, where a lot of the movements need to be felt to be really understood. When students start learning, it is very easy for them to become frustrated with the intricacies of the different shapes, or why they are moving here and not here. They can sometimes see it, or understand the explanations they are given, but they don't actually get it. It takes time and practice to feel what should be happening, and why it should be like that. There is more to it than shapes, but to begin with new students need more help to discover the path.
I also liked this one ...
"If you inadvertently hit your partner in the groin, get out of range and keep moving until he isn't mad anymore."