This is a lesson that bears repeating: Not all quantitative metrics are useful, at least not by themselves. In a post at Consulting 101, Lew Sauder shares a quick example on this subject. It regards arrival times to work and how an employer measured arrivals by the time at which people connected to the network. His story illuminates a larger issue: Quantitative metrics are objective and indisputable, but they are not inherently logical. Metrics must be applied and considered as part of a larger logical framework if they are to be effective. Otherwise, they will be gamed, thus defeating the purpose of having a metric at all.
You can view Sauder’s post here: http://blog.consulting101book.com/quantitative-measurements-gaming-system/