Well, nowadays the oil changes go to the "greenhorns" or "lube techs" at dealerships. And most dealership shops have the oil hoses on retractable lines from the roof. When the lube tech goes to pull the trigger and starts pumping the new oil in, if they don't pay close attention, they can easily overfill in seconds. And, what lube tech wants to lift the vehicle back in the air and remove the drain plug again?