I'm not surprised. I have introduced several people to gaming, both adults and children. I let them all start with the default settings, and I don't even tell them there are settings. Then I observe their movements. I observe whether they consistently (or very often) start looking the wrong way before correcting. If they do that a lot, I change the settings, and it's smooth sailing from there.

So from my anecdotal perspective, explanations based on previous experience make no sense. It had to be something more innate, more related to how our brains are "wired".

Some people invert Y but not X. This is the most surprising to me. Most I've seen invert both. I don't remember having seen someone invert X but not Y.

Personally I invert both, except for games with a mouse to aim (like 3rd person shooters). In that case I invert neither. Go figure.

> Some people invert Y but not X. This is the most surprising to me. Most I've seen invert both. I don't remember having seen someone invert X but not Y.

Interesting, because I've never seen someone invert X. They either invert Y, or neither. Personally I invert Y only in flight games, anything else feels wrong to me.