Project Management: Counting bug inflow and outflow

Cohn, Mike. (2002) "A Measured Reponse: Useful metrics to give managers the numbers to back up project hunches." STQE 4(5):20-25, Sep-Oct.

A few years ago, I was leading a large development group and the leaders of the Quality Assurance team visited me. They said they were ready to provide me any metrics I wanted. AlI I wanted was bugs found vs. bugs fixed day by day for each product along with cumulative bugs outstanding by day. Looking crestfallen, they asked if that was all.

That is all I wanted, a simple metric, that turned out to take a lot of work for them to provide it for dozens of products under development. It tells you how much QA work is getting done, how buggy the product is, whether the bugs are overwhelming the development team as you approach ship date, and so forth. You can largely predict the success of the rollout of a new product by knowing this single metric.

There does not seem to be a lot written about this simple metric. I was happy to see Mike Cohn make it the centerpiece of his article. Recommended.