"If Contact is Lost, Hit Straight Forward"

If  you are in contact with an opponent and contact is suddenly lost, then you are in a dangerous situation because you don't know where the opponent will hit next. The eyes cannot keep up with high speed close range hitting. Therefore the safest thing for you to do upon losing contact is to immediately hit towards the opponent's central axis. Use the fact that the shortest distance between two points is a straight line.

What does this really means?

Often in Sticking hands practice the student gets carried away trying to stick with everything leading to the fault of "chasing hands" rather than hitting. If you think too much on defense then eventually you will get hit. In our mind  Wing Chun's strategy  is mainly to hit. If we are blocked or jammed then we must find another path to strike.  The Sticking Hands helps to create openings for attack. One way to train this principle is to try blindfolded sticking hands. In this case you have no choice but to hit if you no longer feel your partner's arm.