Charles Steinmetz was once called out of retirement by General Electric to help it locate a problem in an intricate system of complex machines. Having spent some time tinkering with and testing various parts of the system, he finally placed a chalk-marked ‘X’ on a small component in one machine. GE’s engineers promptly examined the component, and were amazed to find the defect in the precise location of Steinmetz’s mark.
Some time later, GE received an invoice from the wily engineer – for $10,000. Incredulous, they protested the bill and challenged him to itemize it. Steinmetz did so: “Making one chalk mark: $1,” he wrote. “Knowing where to place it: $9,999.”
Source: IT and Business Alignment: Finding the Mark by Ruby Gates | BetterManagement.com, July 23, 2004