Nintendo's Shigeru Miyamoto has revealed that one of Mario's most recognisable moves, the "B-Dash", began life as an unintended bug in the original NES version of Super Mario Bros. The mechanic, which lets players hold the B button while running to carry momentum across small gaps even after leaving solid ground, was the result of imperfect collision detection rather than deliberate design, yet Miyamoto chose to keep it because it made the game more enjoyable to play.

Speaking in an interview with Casa Brutus magazine, Miyamoto explained that the flawed ground detection let Mario "dash across" gaps unexpectedly, and rather than fix it he decided: "It's fun if he can dash across – let's leave it as is!" The B-Dash has since remained a core part of the series for around 40 years, appearing in recent entries such as Super Mario Bros. Wonder. Miyamoto also disclosed that the franchise's iconic hidden blocks had a similarly accidental origin, having first appeared as a bug in which coins inexplicably materialised in mid-air.