There's a story/joke that everyone who's been in engineering for very long has heard. The one about a company balking at a bill, only to get an itemized one with "knowing where to put the X, $10,000."
It turns out, this story is _TRUE_:
https://www.smithsonianmag.com/history/charles-proteus-steinmetz-the-wizard-of-schenectady-51912022/
Forget Tesla, Steinmetz was the real genius.
@robpike mentioned this in a lecture.