What happens to the board after 300 strokes?

The hazards of hitting the board 300 times are as follows:

1, serious skin damage, leading to bleeding, swelling, cyanosis, infection, etc.

2, nerve and muscle damage, leading to pain, numbness, convulsions, paralysis and so on.

3, psychological and emotional trauma, leading to fear, anxiety, depression, inferiority and so on.

In ancient times, Mr. Xue punished students by slapping their hands with a ruler, which was called a beater or a board.