You drove and pulled up to the gas station to fill your gas tank. You exited your vehicle, opened your gas tank cover, grabbed and put the dispenser nozzle in. You also had to pay at some point.
How can you forget that the hose is still connected to your car when you drive off?
Most gas station I’ve been to in the USA remove the little metal plate that allows the trigger lock to catch, so exactly this doesn’t happen. You have to keep your hand on the handle the entire time or it stops pumping.