Nitpicking
Nitpicking is the act of removing nits (the eggs of lice, generally head lice) from the host's hair. As the nits are cemented to individual hairs, they can be removed with most lice combs and before modern chemical methods.
This is a slow and laborious process, as the root of each individual hair must be examined for infestation. It was largely abandoned as modern chemical methods became available; however, as lice populations can and do develop resistance, manual nitpicking is still often necessary.
Metaphor
As nitpicking inherently requires fastidious, meticulous attention to detail, the term has become appropriated to describe the practice of meticulously searching for minor, even trivial errors in detail (often referred to as "nits" as well). Thus "nitpicking" may be a pejorative term for troubleshooting, proofreading or similar, whose excess could be a psychopathologic form of criticising. The word was coined in early 1900s and came to be used extensively as a metaphor in the mid 1900s post the industrial revolution. The word was also made famous by an Anglo Indian Worker working in the Indian BPO ITES field when being marked down by a Quality Checker. The worker and Quality personnel are now happily married after they buried their hatchet and found nit Picking into each other., see hypercriticism.
