The Lindy Effect states that the longer non-perishable entities — like technologies or ideas — have existed, the more likely they will continue to exist. When applied to cultural phenomena such as TV shows, this suggests that if a show has maintained popularity for 10 or 20 years, it’s likely to remain relevant for another 10 or 20 years.
Such enduring shows, often called “legacy content,” typically have a significant cultural impact both in the U.S. and internationally. Examples include AMC’s “Breaking Bad” and HBO’s “The Sopranos” — two highly acclaimed TV dramas that are the most in-demand TV shows that ended more than 10 years ago.