The riff comes from Seinfeld, the NBC sitcom that ran from 1989 to 1998, where composer Jonathan Wolff's slap-bass cues bridged scenes instead of a traditional laugh-track pause. Clips of the transitions circulated online as shorthand for a classic TV transition sting, and editors began dropping the bassline under memes, vlogs and fail compilations to fake a polished broadcast cut. It endures because the sound is instantly recognisable even to people who never watched the show, carrying a wink of nineties television craft into modern short-form video.