Stop in for a cup of coffee

One of the soda machines at my work place was a bottle dispenser. The selector buttons were marked with

One day one variety ran empty in the machine and there was none in stock to refill it.
One of the employees replaced the bottle cap/marker with and left that portion of the machine empty. I fielded many customer complaints about the empty soda machine. I don't know who did it. None of the customers lost their money. I promise to never do it again.