I burned the tag. It didn't seemed to be used much and of the few times it was used about half were done incorrectly as for my guess of what it was meant to be used for.
As no one seemed to be able to say what it should be used for, it was easier to just burn it.
I have been going through the tags and adding usage guidance statements to those lacking when I came across the human-factors tag and I don't know what the usage case would be.
Sometimes I can find a better tag to switch a bad one out with, but this one is stumping me and Wikipedia isn't much help.
For the questions already tagged with it, I can't find the common denominator.
Does anybody else have ideas of how it should be used?