I've been replacing electrical outlets throughout our 40 year old house because anything you plug into them wants to fall out. I've never had this problem in any home I've ever lived in, but this is baffling me. Can anyone tell me what causes these outlets to fail? I'm guessing who ever built the house put in the cheapest components possible but want to make sure there isn't something else going on. When we built our addition, we hired a license electrician and he sure couldn't answer this mystery.