CA....
FWIW, here’s the explanation in the opening paragraph of the Wikipedia entry for it:
“Moore’s law is the observation that, over the history of computing hardware, the number of transistors on integrated circuits doubles approximately every two years. The period often quoted as “18 months” is due to Intel executive David House, who predicted that period for a doubling in chip performance (being a combination of the effect of more transistors and their being faster).[1]”