@Unixbigot

"The quality assurance engineer knows what is broken at all times. It knows this because it knows what isn't broken. By subtracting what is broken from what isn't, or what is not broken from what is (whichever is greater), it obtains a difference, or deviation.

Management uses deviations to generate corrective commands to drive developers from a position where they weren't to a
position where they shouldn't have been, but now are."