The answer was concealed in 1993 in the old issue of Nintendo Power Magazine in the recently dug enthusiasts.
As it is understood, the editors then returned to engineers who developed controllers directly. They clearly explained that they wanted to divide the buttons basic and secondary.
The lower buttons were accepted as “mother ve and the top buttons were“ additional .. To clarify this for players and developers, the designers used their letter appointments from automatic design systems (CAD): A and B shows Key items and X and Y – Assistant.
Thus, an unusual scheme is fixed and used for more than 30 years. Even in the Switch 2 Nintendo’s controller, he protected the same letters.
Microsoft, the “Nindic” layout of the players who are accustomed to the A and B, although changing the place of the system adopted the system.
Source: Ferra

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