Why I use the implemented definition of "better" in favour of my (admittedly completely subjective) definition? If you surveyed people's definitions of "better

Why I use the implemented definition of "better" in favour of my (admittedly completely subjective) definition? If you surveyed people's definitions of "better [thing that they care about]" you'd get a lot of different answers, but I suspect few would say "more people like it" (even if an algorithm based on "more people like it" would be good at finding things they think are better).