First, I am not aware of any operating systems that are developed using agile methods, and second the empirical evidence is in that agile improves quality, so it would be better if they were.
According to this study, you can measure a team's progress and ability with:
* number of production deployments per day (want higher numbers)
* average time to convert a request into a deployed solution (want lower numbers)
* average time to restore broken service (want lower numbers)
* average number of bugfixes per deployment (want lower numbers)
I am curious about other studies in this area and if there is overlapping or conflicting information.
This is well researched and discussed in Nicole Forsgren's book: Accelerate: The Science of Lean Software and DevOps: Building and Scaling High Performing Technology Organizations
If it takes 10 people and six hours to accomplish the release of even the smallest of features, then it sounds like there's a bug with your "ship fast" feature and the team should invest some or all of its resources in fixing that. You probably can't do it over night, but you gotta chip away at it over time at the very least.
If you are looking for justification backed up by real world numbers, I highly recommend the book "Accelerate" by Nicole Forsgren, et.al.
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