What key metrics do you use to evaluate DevOps processes?

To evaluate the effectiveness of DevOps processes, I use the following key metrics:

• Deployment Frequency — how often releases or deployments occur in production.
• Mean Time to Recovery (MTTR) — how much time it takes to restore the system after a failure.
• Percentage of successful releases — the proportion of releases without critical errors.
• Lead Time for Changes — the time from writing code to its successful deployment.

These metrics help understand how quickly and reliably the team delivers changes to users and how stable the infrastructure operates.