PlayStation was originally X = B O = A Because in Japan they use a circle to mean the same thing as in English a check mark is used. That is: "yes", or "correct". The cross means "no", or "wrong" in the same context in English and Japanese.
At some point the English language PlayStation games started flipping the meaning of X and O. Not sure why. Maybe to align with Xbox? So eventually Sony changed it in Japan too in order to standardise globally.