Lindy Effect

a theory that the future life expectancy of some non-perishable things like a technology or an idea is proportional to their current age, so that every additional period of survival implies a longer remaining life expectancy

First presented by Mandelbrot in his 1982 book The Fractal Geometry of Nature. Later modernized and referenced by Nassim Taleb in The Black Swan: The Impact of the Highly Improbable (2007), and Antifragile: Things That Gain from Disorder (2012).

"If a book has been in print for forty years, I can expect it to be in print for another forty years. But, and that is the main difference, if it survives another decade, then it will be expected to be in print another fifty years. This, simply, as a rule, tells you why things that have been around for a long time are not "aging" like persons, but "aging" in reverse."