It just means that a false positive rate is as dangerous as a false negative rate. Just issuing a warning doesn't come for free when you are designing a security system.

This is very well illustrated in the fable Boy who cried false positive.

that sounds like a character from Harry Potter and the Methods of Rationality.

Any lessons in HPMOR are also going to be found in traditional works.

I was interested to find a discussion of the trolley problem in a book of out-of-copyright Norwegian-region folk tales (in English translation) that Amazon recommended.

False positive? How did you know?