This sound comes from Mario Kart 8, Nintendo's kart racing game first released in 2014, and later kept popular through Mario Kart 8 Deluxe on Switch. The countdown became a familiar audio cue in gameplay clips, speedrun content and reaction edits because it clearly signals that action is about to start. Online, creators use it as a gaming equivalent of an alarm or the Inception Button, especially when a scene needs a playful but tense lead-in.