when a solution for solving a problem could actually make it worse

The term 'Cobra effect' stems from an anecdote set at the time of British rule of colonial India. The British government was concerned about the number of venomous cobra snakes. The Government therefore offered a reward for every dead snake. Initially this was a successful strategy as large numbers of snakes were killed for the reward. Eventually however the Indians began to breed cobras for the income.

A similar incident occurred in Hanoi, under French colonial rule, where a program paying people a bounty for each rat pelt handed in was intended to exterminate rats. Instead, it led to the farming of rats.