There is a small town on the East Coast that has 2 barbershops each with a single barber, and on opposite sides of town. The barbershop in the good part of town is immaculate. The floors and windows are washed and the air is fresh. The barber is very friendly, always smiling, he has shined shoes, a nice head of hair, and a clean dress shirt. The barbershop in the bad part of town is a mess. The entire barbershop is covered with a layer of dirt, and the air smells of trash. The barber always has a frown on his face. His skin is oily, his hair is ragged, and there are always stains visible on his shirt. A man comes into town and hears of both barbershops and the man decides to go to the dirty barbershop in the bad part of town. Why does he do this?
The clean-cut barber must have his hair cut by the dirty barber and the dirty barber by the clean-cut barber. So it's obvious that the dirty barber gives a better haircut.