Proxy Metric

A metric the vendor can count that approximates a result the vendor cannot count. A resolution counter records that a session closed; it does not record whether the customer's problem stayed solved. A qualified lead records that a record met a rule; it does not record whether anyone wanted to buy. The proxy is not a flaw to be engineered away, since some proxy is always required. What matters is whether both sides understand the gap and agree in advance who absorbs it.