The appliance and the hole.
The appliance and your home. It’s the hole that affects the entry of the pests. Often the wall socket is surrounded by the cover but may still allow pests. The cover may fit tightly but the technique is to fill in that gap with caulking. By sealing the outside, you stop the pests outside. But if there is a gap and they encounter it they may get in. Home-sealing is still the best option and helps to add one more line of defense against the possible invasion of pests.
Home-sealing eliminates the holes or crack that scorpions, ants and spiders may take into your home. You can do your own sealing or hire a professional company to do it. It is better to be done in the winter if you you-re doing it as it HOT and messy. You can do the inside any ole time and its easy enough to do, pull the cover down or off and caulk.