Campbell's Law
High-stakes use of social indicators can create pressure to distort the processes they measure.
The Mechanism: Donald Campbell argued that the more a quantitative indicator is used for social decision-making, the greater the pressure to corrupt it and the processes it monitors. The risk depends on how tightly rewards are tied to the metric.
The Philosophical Pivot: A public number can appear impartial while redirecting human effort toward what is easiest to measure. What was designed to reflect a goal can gradually replace the goal.
The Horizon: Auditing, multiple measures, and qualitative review can reduce distortion, but no measurement system is immune to incentives. Institutions must examine how people adapt to evaluation.
Metrics can reveal inequity and guide resources; rejecting them entirely can hide problems too. The task is to use numbers without mistaking them for complete representations.
A measure is trustworthy only while people remain willing to ask what it stopped measuring.
The more power a number carries, the more carefully we must inspect what it leaves out.
If people are rewarded for this metric, how might their behavior change in ways the metric cannot see?