Alcohol
A guy goes into a bar and sits down next to a guy who's obviously been drinking for a while.
The drunk gets up from his stool to go to the bathroom and falls down 3 times.
The guy says to himself "I'll help this guy get home safely" and helps him out to his car
The guy falls down five more times.
He drives him up to the address on his license, takes him up to the door.
The guy falls down 8 times on the way...and rings the bell.
A lady answers the door and says "Oh how nice, you brought home Harry. But what did you do with his wheelchair?"