One day a school was faced with a unique problem. Several girls would put their lipstick on in the bathroom. The problem was, after they put on their lipstick they would press their lips to the mirrors leaving dozens of little lip prints.
The principal finally decided that something had to be done. Calling several girls to the bathroom, she met them there with the custodian. She explained that all these lip prints were causing a major problem for the custodian who had to clean the mirrors every day.
To demonstrate how much work they were making for the custodian, she asked him to clean one of the mirrors while the girls watched.
The custodian took a long-handled brush, dipped it into the nearest toilet, and proceeded to scrub the mirror.
The problem of lip prints on the mirrors was completely eliminated.