I had another interesting question from a reader that I’m getting to in the blog today:

I was ready some of your excellent webinars, specially about the defect metrics, So my question is: Is there any benchmark data about defects severity, and also about reopen defects.?

I would really appreciate if you can guide me where I Can find this data.

Note: the purpose of this data is to measure and compare our results against the benchmark.

Tomas Gotes

Thanks for the question, Tomas.  In terms of defect severity, unfortunately there are no standard, common definitions for severity in the industry yet.  So, any metrics that showed aggregated data from multiple organizations would probably be rather questionable.  That said, you might check out Capers Jones’ excellent book, The Economics of Software Quality, which, as I recall from reviewing it, had some interesting analysis here.

In terms of defect report re-open rates, our target during assessments is 5% or less.  Some amount of defect report re-open seems inevitable, since test environments and data are generally more representative of production than are the developer’s environments.  However, there is a significant risk of schedule delay, as well as significant inefficiency (due to an additional layer of rework), when the defect re-open rate gets too high.