It's only a trap if you don't repurpose it.

optimism

Economist Charles Goodhart observed that once a statistical regularity is used as a policy target, it tends to break down under the pressure of that very use. Anthropologist Marilyn Strathern later distilled the idea into the phrase now commonly invoked: “when a measure becomes a target, it ceases to be a good measure.” Goodhart’s original context was monetary policy, but the insight travels well beyond it. Measures are valuable because they summarize complex information, allowing people to make decisions in situations where perfect knowledge is impossible. Problems arise, however, once those measures become the basis for rewards or punishments. At that point, organizations have the incentive to improve whatever indicator is being observed.

econ

> # The Target Trap
>
> Economist Charles Goodhart observed that once a statistical regularity is used as a policy target, it tends to break down under the pressure of that very use. Anthropologist Marilyn Strathern later distilled the idea into the phrase now commonly invoked: “when a measure becomes a target, it ceases to be a good measure.” Goodhart’s original context was monetary policy, but the insight travels well beyond it. Measures are valuable because they summarize complex information, allowing people to make decisions in situations where perfect knowledge is impossible. Problems arise, however, once those measures become the basis for rewards or punishments. At that point, organizations have the incentive to improve whatever indicator is being observed.
> 
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