I think about this in a different way that leads me to believe that the
++ < -- organization makes perfect sense. Namely,
++ votes are much more common than
-- votes. Thus it makes sense to have
++ appear at the beginning of the voting-buttons list rather than at the end. (It does make me wonder if I'd want the buttons in reverse order if I were reading right to left.)
I suppose you could also ask why the English expression is "plus-or-minus x" rather than "minus-or-plus x". Negative-precedes-positive may correspond to the way we visualize a number line, but I simply don't think it maps to our day-to-day expectations in a case like this. The fact that you used it for a year without noticing is another sign, imho.
$perlmonks{seattlejohn} = 'John Clyman';