I picked 25 mugs the porcelain factory had rejected as defective and painted smileys on them.
Most were marked unsellable because of flaws almost invisible to the eye that had no effect on how they worked.
Within a week I sold them all on Instagram for the price of flawless ones. The point was the absurdity of excessive quality control — and how quickly things that differ get removed. The flaw is often what turns an ordinary mug into a particular one.