[pron]

Amazon do formally verify AWS (they use TLA+), which is probably why this failure is a human error. Of course, you could expand the formal analysis of the system to include all possible operator interactions, but you'll need to draw the line at some point. NASA certainly makes human errors that result in catastrophic failures. The Challenger disaster was also a result of human error to a large degree[1]; to quote Wikipedia: "The Rogers Commission found NASA's organizational culture and decision-making processes had been key contributing factors to the accident, with the agency violating its own safety rules."

[1]: https://en.wikipedia.org/wiki/Space_Shuttle_Challenger_disas...