See also deployability

Four key devops metrics:

  1. Lead time for changes: the length of time between when a code change is committed to the trunk branch and when it is in a deployable state.
  2. Change failure rate: the percentage of code changes that require hot fixes or other remediation after production.
  3. Deployment frequency: how often new code is deployed into production  
  4. Mean time to recovery: how long it takes to recover from a partial service interruption or total failure.

quoted from Atlassian

For a slightly more detailed introduction, see the four metrics themselves: