Productive throughput and efficiency
This section gives critical metrics on code quality, and the overall productivity of the work being committed.
Code churn: Code that is deleted/rewritten within 21 days of merging is called code churn or rework
Productive Throughput and Efficiency: Code that is not churned, that is, code that does not get rewritten/deleted within than 21 days.
Efficiency: Percentage of Code that does not get churned.