A dirty house
When the house is dirty, the cockroaches, ants and flies will make it their homes. They will infest a dirty house to run riots in every nick and corner. They will become irritants to the owners. The owners can start spraying them and see their dead carcasses littering everywhere. But they will not go away. More will return to occupy the dirty house.
A more effective way is to clean the house, put it in order. Get rid of bad habits, dirty habits, disorders, and impose strict discipline and good behavior. When a house is in order, when a house is clean and not shitty, the roaches, rats, flies and ants will find it unsuitable or inhospitable to stay. They will go away naturally and will not reappear.
Buying insecticide spray, swaps, rat poison, roach traps, is only a temporary solution. The real and long lasting solution is to keep the house clean. And gluttony, eating too much and dropping crumbs everywhere, too much unfinished and unable to consume food, too will cause a house to become unhealthy and smelly. That’s when the irritating pests will return to haunt the owner.
Keep the house clean and in good order. And don’t anyhow bring in fair weather friends who are only interested in sponging and feasting in the house and with one foot outside, ready to scoot when the buffet is gone.