Why is monthly pest control necessary?
The response to this question requires some clarification. The answer is it depends on what the pest control person is treating. For the most part you do not need monthly pest control unless you are treating an infestation that requires immediate follow up. Remember pest control service does not necessarily mean apply a pesticide.
Food establishments (some more than others) require monthly pest control service. Hotels and places of high people traffic, animal shelters, places where food and harborage are an attractant to insects require inspection and if required, treatment.