This is a similar story.

When ATMs were introduced in Canada in the 70s/80s, it was common to believe they were infallible. When customers claimed they were short-changed by machines, often they were prosecuted for fraud or attempted theft.

I'm sure HNers can think of dozens of ways a machine could be wrong ...

https://en.wikipedia.org/wiki/Automated_teller_machine

Also, regarding the Postmaster article, note that somebody working on that project would likely face great difficulty in convincing anybody there was a systems problem.