The real waste economy

There is an old story according to which the British government when deciding what to do about an infestation with cobras in their Indian colony, put up a monetary reward for every dead cobra. The policy worked at first, but then, people increasingly started to game the system by breeding cobras and killing them for profit. When the government understood its mistake, it decided to remove the reward which lead to the cobra breeders to release the snakes into the wild, leading to an even bigger cobra population than initially. The cobra effect which the story describes goes under many different names in politics, sociology and economics but the idea is the same – if a metric becomes the target it will be gamed or corrupted.