Continuing on anthonyCGs point, besides courtesy not resigning makes no sense from a chess development point of view.
"But mike, wouldn't never resigning increase your winning percentage?"
Well yes, in theroy, especially since many resign too soon. But the gain will be short term, since you aren't actually getting better (another important point), you are just skewing the rating system in your favor. In the long term, not resigning is a bad decision because playing out completely lost games teaches you peanuts compared to starting a new game or studying. Furthermore, if you play OTB and never resign, many players WILL refuse to play you, lowering your skill level even further (probably because you take too long to play/you made them late for piano lessons or something)
I hardly ever resign, but I don't see why that would be annoying at all, I think it's better to have won by Checkmate than Resignation.
I really don't get it.