Probably the last man who knew how it worked had been tortured to death years before. Or as soon as it was installed. Killing the creator was a traditional method of patent-protection.
Terry PratchettGranny Weatherwax was not lost. She wasn't the kind of person who ever became lost. It was just that, at the moment, while she knew exactly where SHE was, she didn't know the position of anywhere else.
Terry PratchettI try to make computers say things like You have 60 seconds to achieve safe distance.
Terry Pratchett