Quote from “Codermetrics” by Jonathan Alexander:

To evaluate whether a metric itself is good or bad, you can ask yourself the following questions:

• Is the metric relatively easy to describe and understand?

• Can the metric show me something I don’t already know?

• Does the metric clearly relate to a goal I care about?

If the answer to any of the above questions is clearly no, then the metric either needs more work, or it should probably be discarded.