Rented a U-haul once to help someone move their furniture. Picked it up in Boston. started driving up INT 93. It was an old rickety truck, brakes barely worked, wobbled from side to side.. this was even before anything was loaded. so on 93, driving out of Boston, there was a loud BANG and a loud sound of air rushing in... there was no place to stop so I had to keep driving until there was an emergency lane to pull over.
5 miles later, I pull over and get out of the truck. the back door was completely open.
They hadn't latched it properly before they gave me the keys to the truck.
to makes things worse, there was a wheel dolly on the floor near the door. It could have easily rolled out the back and killed somebody.
Lesson learned. before you drive away, check the back door to ensure it is properly latched!