Change Fail Rate
less than a minute
The percentage of changes that result in negative customer impact, or rollback.
changeFailRate = failedChangeCount / changeCount
What is the intended behavior?
Reduce the percentage of failed changes.
How to improve it
- Release more, smaller changes to make quality steps more effective and reduce the impact of failure.
- Identify root cause for each failure and improve the automated quality checks.
How to game it
- Deploy fixes without recording the defect.
- Create defect review meetings and re-classify defects as feature requests.
- Re-deploy the latest working version to increase deploy count.
Metrics to use in combination with this metric to prevent unintended consequences.
- Delivery frequency can decrease if focus is placed on “zero defect” changes.
- Defect rates can increase as reduced delivery frequency increases code change batch size and delivery risk.
- “Accelerate” Ch2: Measuring Performance - Nicole Forsgren PhD, Jez Humble & Gene Kim
Last modified October 13, 2022: Corrected broken links (#8) (d324154)