What would it mean for it to matter? Does it matter to wikipedia or those voting what we discuss here? Very unlikely.
But internally for an individual trying to understand why someone else would make a choice that they themselves would not, it does matter for improving our own understanding and empathy. If you choose B but I would choose A if I were in your shame shoes, then either I don't understand your shoes well enough to call them the same or I'm missing some understanding of the issue. Even in the case where we could objectively determine that A was the correct choice, if I don't understand why you choose B then I'm still missing something about the situation.
This could be just to sate curiosity, but enough instances of similar behavior allows us to better understand and empathize with others. When it comes to an issue we think we understand better than most other issues, to have a disagreement in what we would've done is much more striking and indicative of some flaw in our understanding. If this was a bunch of surgeons picking some post-surgery recovery practice to recommend, I could easily dismiss the difference in me not understanding the topic well enough. If it is instead a kid picking a different answer than I would on a test after I helped tutor them, then it is a much clearer indication that I'm missing something in tutoring. Maybe a bad assumption about prior knowledge, maybe an unknown to me issue with test taking like them having significant test anxiety that doesn't show up in tutoring, ect.