I am not so naive to think that this wasn't asked/discussed, but I have not found a close enough fit to my question (yet). Also, I will appreciate any improvements to my question (also as per language).
So: I guess that naively, as an outsider, one would think that the most upvotes next to an answer should mean that the answer is the most correct one, so "correctness of the answer" could be the answer to my question. However, after some experience with the site, one can argue that "usefulness" is a much better concept, both intuitively and given the broad/fuzzy nature of questions asked (sometimes the answer have rather the character of a discussion, or even an opinion on some SE sites). As far as I understand, this is the reason behind the current paradigm: "This answer is useful." appears when hovering above the upvote button. (I wonder, though, what the prehistory of this was.)
as per correctness - not all readers have the knowledge to judge the correctness of an answer (which can be evaluated quite objectively in case of e.g mathematics or computer code, which is even more straighforward), partly because they didn't know the answer in the first place and that is why they landed there, which touches the author of the question, too.
as per usefulness - it is not so clear whether usefulness is meant with respect to the ability to solve/understand the solution of the question as asked by author, or to solve a related question of a user who was directed to this question because of a similar, but maybe not identical, problem.
Perhaps a more correct interpretation (on some SE sites) of the upvotes is something like "plausibility" of the answer, how correct/useful it SEEMS to people, as far as they can judge.
Also, as most upvoted answers tend to be most read and hence most upvoted, a positive feedback loop kicks is. How this would be taken into consideration in the interpretation of the upvote button?
So our hypotheses are (please feel free to add):
- most useful (currently accepted paradigm)
- most correct (not always a measurable criteria)
- most plausible (appearing to be correct)
- most relevant?
- best explained (could still be incorrect, though)
- best by some other metric ? ...
I realize this question is far from being perfect/clear/complete, so feel free to through some ideas. Maybe "usefulness" is just fine and all this is superfluous.
Related: How does accepting an answer work?