The sound comes from the long North American stadium organ tradition in baseball, hockey and basketball, where organists prompt crowd chants with short, recognizable riffs between plays. This Let's Go pattern became a staple because its rhythm maps neatly onto two-syllable team names and city names, letting thousands chant in unison. As game highlights and fan edits moved to social video, the riff was lifted as a ready-made hype cue. It remains popular because it signals support and momentum instantly, even in a clip with no actual crowd.