The cleanliness does not necessarily show. A plate might look clean , but it might be infested with tons of germs , bacteria , viruses .
Even in USA the other day I was watching a news pieces which showed that the food at many restaurants had traces of human fecal matter in it. Eeeeeeeew. According to that news article it was due to the fact the the restaurant employees were not washing their hands properly before returning to their work stations after using rest rooms. baaaaaarrrrrrrrffffffffffff.