Because in the night when ghosts and gods haunt, if there is water in the bowl, it will be enjoyed by ghosts and gods, resulting in sufficient yin, which is not good for people. Especially if you don't wash the dishes at night, it is especially bad to add bubbles to the bowl. If the bowl is clean, empty the water.
In fact, this statement is mainly to persuade people to love cleanliness, wash dirty bowls in time, and don't leave them until the next day; On the one hand, if the bowl is dirty, it will affect the mood of the next day; Secondly, if there is water in the bowl, it is not volatile, which is not only easy to breed bacteria, but also provides survival resources for cockroaches, which is unsanitary.
These are the reasons for washing dishes in time at night and leaving no water in the bowl.