Hundreds of aspects of software products, projects, and processes can be measured. It’s easy to choose too many different data items to be collected when beginning a metrics program. Until a measurement mind-set is established in the organization, expect resistance to both the concept of measuring software and the time required to collect, report, and interpret the data. A long list of metrics might scare off some of the managers and practitioners whose participation is required for the program to succeed.

I once worked in an organization that had a comprehensive, large-scale metrics program. More than 100 product-development projects were expected to report quite a lot of data to a centralized office. This office generated massive quarterly reports containing dozens of charts that they distributed throughout the organization. After a couple of years a survey revealed that virtually no one was using any of the contents in these reports! The project managers were simply overwhelmed with the data and did not find it useful. As a consequence, the entire program was terminated.

Begin growing your measurement culture by selecting a fairly small, balanced set of software metrics. By balanced, I mean that you are measuring several complementary aspects of your work, such as quality, effort, size, and schedule. See Chapter 12, "A Software Metrics Primer," for some specific recommendations. You can gradually expand the metrics suite as your team members learn what the metrics program is all about and how the data will (and will not) be used. Start simple and build on your successes.

The participants in the metrics program must understand why the requested metrics are valuable before they’ll be willing to do their part. For each metric you propose, ask, "What can we do differently if we have this data?" If you can’t come up with an answer, perhaps you don’t need to measure that particular item right now. Expand the program once the participants are in the habit of using the data they collect to help them understand their work and make better decisions.