Two Blondes With Hammers...
Rachel and Deborah, were doing some carpenter work on a Habitat for >Humanity house. Rachel, who was nailing down house siding, would reach >into her nail pouch, pull out a nail and either toss it over her shoulder >or nail it in.
Deborah, figuring this was worth looking into, asked, "Why are you >throwing those nails away?"
Rachel explained, "When I pull a nail out of my pouch, about half of them > have the head on the wrong end and I throw them away."
Deborah got completely upset and yelled, "You moron! Those nails aren't >defective! They're for the other side of the house!"