Via "Let's set a new standard" I discovered Goodhart's law. I've long been arguing, err, OK, ranting that the setting of targets in an organization is usually counter-productive, because people will very soon learn to game the system, meeting the targets without actually doing what the organization is supposed to be doing. Think SATs, hospital waiting lists, arrest figures, the list goes on.
It's nice to know that the effect has a name.
Dan Abel had a similar discovery recently, when he stumbled on the term Moral Hazard, an effect he'd noticed before.