It's not really a simple matter of trust, though. To take the example of the 'poka yoke' system that was posted here last week: is it because of a lack of trust

It's not really a simple matter of trust, though. To take the example of the 'poka yoke' system that was posted here last week: is it because of a lack of trust that equipment operators are required to visually signal to themselves the action they will perform? Or is it because it's a simple and easy way to avoid basic operator error? "We trust our engineers to merge code and not break production," is not the same as "we require peer review of changes to production, and/or QA, to mitigate human error." Or more simply, trust but verify. Not every team will have a CI/CD pipeline that can effectively automate the 'verify' step. Nobody on my team, for example, is worried about being required to have n approving reviews. If nothing else, it's a relief if it means we're not paged at 3am to fix something we deployed without fully checking.