This problem is canonized in a principle known as Goodhart’s law. While Goodhart’s original formulation is a bit opaque,*8 anthropologist Marilyn Strathern rephrased it clearly and concisely: When a measure becomes a target, it ceases to be a good measure. In other words, if sufficient rewards are attached to some measure, people will find ways to increase their scores one way or another, and in doing so will undercut the value of the measure for assessing what it was originally designed to assess.
