Math Says Yes

Concept

Goodhart's Law

Goodhart's law says that when a measure becomes a target, it tends to stop being a good measure. People optimize what is rewarded, so the metric can improve while the thing it was meant to represent gets worse.

Lessons

A target metric being pulled upward while behavior bends around it.

Metrics Change Behavior

A metric can be a useful signal until people are rewarded for moving it; then the signal often gets gamed.

Related Facts

Risk & Decisions

A dashboard gauge hitting a target while warning lights show quality falling.

Goodhart's law: when a number becomes a target, it starts to lie

A metric can be useful until people are rewarded for moving it. Then the number may improve while the real goal gets worse.