Less depressing example. A country (I think it was India but my memory is hazy and I’m too lazy to go google it right now) had a problem with a certain venomous snake. They decided to offer a bounty for every snake corpse brought to them. The goal was to incentivise people to hunt snakes. What actually happened was people started breeding the snakes to turn in for the bounties. They realized the program wasn’t working and cancelled it at which point the breeders dumped their snakes into the wild making the whole situation even worse.