如愚见指月，观指不观月

#古德哈特定律（Goodhart's Law）#

当一个衡量指标成为目标，它就不再是一个好指标。
When a measure becomes a target, it ceases to be a good measure.

衡量一旦变成考核目标，就会诱发博弈，从而失去衡量真实表现的有效性。