Nintendo's D-pad made arcade movement pocket-sized

Portable games needed arcade-style movement without an arcade joystick. Separate buttons confused players and a protruding stick was bulky and fragile in a handheld device.

Nintendo's answer was a multi-directional switch: a cross-shaped key top, a central fulcrum, and four conductive rubber contacts. One thumb could rock the cross toward up, down, left, or right without moving across separate buttons.

The idea moved from Game & Watch into the NES controller. The Science Museum notes that the cross-shaped D-pad was less bulky than joysticks and became an industry standard still present on modern controllers.

Put four directions under one rocking cross

It matched the real task: most 2D games needed four crisp directions, not a full analog lever.

The shared cross prevented the user from hunting for separate buttons while keeping the part low-profile.

Rubber contacts gave a cheap, repeatable switch that survived pocket and living-room use.

When the job is discrete, do not miniaturize the old interface. Recast the actions into a shape the body can operate reliably.

The NES controller made the D-pad the default vocabulary of console control. Competitors could vary the shape, but the thumb-operated directional pad became the assumed input for 2D games and menu navigation.