TIL that a USB-A connector is, for all practical purposes, a quantum object It isn't. But it sure behaves like one, collapsing into a definite orientation only after you've committed to the wrong one. : it exists in a superposition of “right way up” and “upside down” until the exact moment you try to plug it in, at which point it collapses into whichever state guarantees failure.
The USB Implementers Forum The USB Implementers Forum is the industry group that actually maintains the USB spec. They gave us USB-C, which is reversible - proof they knew about the problem all along. designed the connector with a helpful little logo on top to indicate the correct orientation. This logo is purely decorative. It cannot be seen by the human eye under normal desk lighting, under a desk, or ever, because the port is always facing away from you, mounted on the back of a tower, three feet behind a tangle of other cables.
The commonly cited fix is the “flip twice” heuristic Plug it in wrong, flip it, plug it in wrong again, flip it back to the original orientation you already tried - and now it works. Nobody has a good explanation for this. Several do not want one. : if it doesn’t go in, flip it. If it still doesn’t go in, flip it again and it will work, despite this being the exact orientation that failed the first time. This is not a joke. This is empirically how it goes, every time, for everyone, forever.
The only known permanent fix is USB-C, which fixed the orientation problem by making the connector reversible - and then introduced an entirely new failure mode where you insert it correctly on the first try and are so unsettled by the experience that you unplug it immediately to check.