That means their use requires significant analytical skills, both to collect the data and to analyze the results. Conformance measurements are highly susceptible to misuse or misinterpretation. Most measurements require some understanding in order to be used well. Even very conformance-oriented measurements can be useful. But they can require hard work, and extraordinary analysts, to make sure they're interpreted properly.
Extraordinary analysts are in short supply.
Identify ways that your measurements can mislead people in your organization. Based on that analysis, identify the extent to which each measurement is a conformance measurement. Where possible, replace your conformance measurements with more clear-cut performance or operational measurements. Buffer management is usually a good replacement for more traditional schedule performance tracking. For those conformance measurements you keep, identify and justify those circumstances under which they should really provoke action or concern.