Tapping is a part of blocking
The main idea with tapping is to lead the opponents attack away from you, and at the same time create a opening for counter attack.
Tapping is not a big movement, it’s just a minimum movement to lead the attack away from you.
The reason to just use small movements is just that the opponent can attack you with several attack after each other, and if you guard is open then you will be hit with the second or third attack.
Tapping is also an entry to trapping and locking, because if you lead the attack in the direction that you want. Then you will be able counter the way you want.
Tapping can be a part of the manupulation of the opponet.
If you look at tapping you will see a lot of the tapping is steering the attack so you will get on the outside of the opponent centreline. Then you will have the centreline against the opponent, and the opponent will have the centreline away from you.
If you tap on the inside, then you are in a danger zone. So you ned to follow up right away. It’s a good position to be in if you know what you are doing. You have a lot of open zones to attack, but you are closer to the opponents counters. If you do like Whing Chun, where they tap and hit at the same time. The you will have a happened ending.