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How I found I need a right handed joystick.
I first started gaming when I was 6 with the Colecovision. I was exposed to an Atari 2600 at a neighbor's house when young. The Atari joystick had the button on the left, so that is a right handed joystick. The Colecovision was designed to be ambidextrous. Not necessarily gaming optical, but ambidextrous nonetheless. In the Atari 2600, some enterprising people made 2 button joysticks, where there was a button on the left and right, and they both did the same thing. Others made 9-pin to 9-pin "leftie Adapters." Atari 800 games from a couple different companies had "left handed mode", press L on the keyboard (Shift L for Player 2) and you toggle into and out of left handed mode, just rotate the joystick 90 degrees.
Then Atari nearly ruined the industry and in the US, Nintendo picked up 95% of the pieces, Sega has 3%, Atari, under new owners, had 1%, and Intelliviison, surviving the crash, took over from Mattel and had 1% of NEW sales. When Nintendo decided to make the D-Pad, originally the patent for for movement-right. Independently, because of a corporate decision to recycle Radarscope machines into Donkey Kong, the cheapest thing to do was to leave it left handed. Most of the high scorers AT THE TIME, based on the anecdotal evidence I saw in the arcades, were crossing their wrists. I don't know if the left-handedness was left in intentionally to milk more quarters for the arcade owners, and that was seen as desirous. When it came time to make the home system, they decided to keep it left handed instead of having a 180 degree invertible pad for 2 buttons a crosspad and 2 auxiliary buttons. Their goal was to come out cheap and invertibility was too expensive.
Granted, Joypads are not that bad, left or right handed. It was doable. I came up with a trick that helped me do some things my friends couldn't on Mega Man that only an older borther and a friend of his can do normally with a thumb, independently control jump and fire by using 2 fingers. And the way I did that was to put the controller on the carpet. And for the NES, that was cool. For the directions I used my left index and Middle finger to coordinate diagonals. That worked well for the Genesis. It wasn't until the Super NES where I HAD to use my thumbs thanks to shoulder pads.
One Christmas in the 80s, My mom and dad took me to a furniture store where they had demoed an NES Advantage. The game played while demoing it was Super Mario Bros. That would definitely sell the game and the console. The joystick not so much. First it advertises slo mo and rapid fire. If your goal was to sell joysticks, that would be the last game I'd pick to demo it. I also found left handed joysticks awkward at the time. Literally the only time I play leftie is if either the left fire was broken or it didn't give me a choice. I reacted as such. Little did I know they already paid for one and wanted to see my reaction. My rental store had Pac Mania and I rented a joystick for that, and it was right handed, one of those Beeshu models. I did just as good at home as in the arcade. So I understand why they'd think I'd like the NES advantage. I took it, tried the rapid fire and slo mo for other games and it SOMETIMES works well, but I never used it as a default controller back in the day.