What's so particular about hanging clocks and geomantic omen in restaurants?

To create a healthy feng shui, we should avoid looking up and not looking down. We know that the bell and the tail are homophonic, so it is bound to be bad to look up at the implication of the clock. Even if the wall clock will bring us exorcism, it will do harm to the body if it is not placed correctly. In the kitchen wall clock geomantic omen, the position of the wall clock should not be in the direction towards the kitchen door, which will threaten the health of family members, especially those who often go in and out of the kitchen.