A tee shirt shop put out a sign that read "Tee shirt sale - 12 tees with a 1 color print - $10.00 each. 36 shirts for 11.00 each. People came in for the sale and imediatly complained about the mistake and wanted them all for 9.00 each. Time and time again, all day long this happened. Each time, the tee shirt guy would agree to the price.
A neighbor business saw this and asked, aren't you going to fix your mistake? The tee shirt guy said " what mistake"? Before I put this sign up, nobody ever bought more than 12 shirts.