We’re back again with outstanding questions from our Agile Metrics Webinar. This question relates to Defect Aging.

Q: Slide 63 – Is this also called Defect Age?
A: Yes, what we term as Time to Fix is equivalent to Defect Age, but ours is a little different with a different emphasis. We are interested in what the end user thinks as the time to fix a defect once they report it. They don’t care about ‘Defect Age’. They care about how long did it take to fix things. Defect Aging is not part of an end users vocabulary.

Furthermore, with Defect Age, you could measure all the defects that you have fixed during the life of the product. This would include those 2 months ago, those from 2 sprints ago, those found while in development and those found in production. Our emphasis is on what is found in production.

Additionally, some may count defect aging times to include those pre-production. We only count post-production defects. Firstly because those usually actually get a real defect report as they are usually reported by the end user. And secondly, with agile, defects found and fixed within a sprint may not be documented if at all, and we don’t want to burden the process by saying ‘all’ defects need to be logged for the sake of our metric.

Lastly, we want to focus on the quality ‘felt’ by the end user. So even small defects that an end user experiences should be counted. To get a more true picture of the end user impact, we could weight defect aging with higher priority defects getting more weighting.