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 leaves. A few days later, the same guy sticks his head in the door and asks, 'How long before I get a haircut?' The barber looks around the shop full of customers and says, 'About two hours.' The guy leaves. 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