Is it ethical to measure people?

We at SourceKibitzer believe that people measurement is by no means unethical. But, people evaluation using measurements without knowing the context and applying intelligence and common sense is dangerous. From our experience, outstanding developers are even glad to be measured as this provides them with additional feedback on their performance. In the end every employee gets measured by a certain salary level. We think, that it is much more ethical to complement management's perception with objective information.

How do you feel about that?