The loss of MCO is actually a very interesting story about both engineering culture (engineers noticed a problem but the organization didn’t respond to investigate/fix it) and the conversion to metric. The root came from NASA deciding to use metric on this project and a contractor using the wrong units. But it’s the kind of thing that the process should be able to catch and handle. It bugs me to dismiss this failure as “haha why doesn’t NASA use metric” because not only is it a direct result of NASA switching to metric, there are really good engineering lessons that get ignored.