A guy sticks his head in the barber shop and asks, "How long before I can get a haircut?" The barber looks around the shop and says, "About two hours." The guy walks out.
A few days later, the same guy sticks his head in the door and asks, "How long before I can get a haircut?" The barber looks around the shop full of customers and says, "About two hours." Once again, the guy leaves the shop.
A week later, the same guy sticks his head in the shop and asks, "How long before I can get a haircut?" The barber looks around the shop and says, "About an hour and a half." Again, the guy walks out.
The barber is getting curious. He looks over at a friend in the shop and says, "Hey Bill, follow that guy and see where he goes."
A little while later, Bill comes back into the shop laughing. The barber asks, "Bill, where did the guy go when he left here?"
"To your house."