It is divided into the following two reasons:
1. Do not look in the mirror after 12 o'clock in the evening. Our human body is composed of three souls and seven souls. At night, yin and yang Damn, it’s easy to see bad things when you look in the mirror frequently at this time.
2. Chinese Feng Shui theory believes that mirrors should not be placed in the bedroom. Mirrors are called "light evil" in Feng Shui and are a tool to avoid evil spirits.