If you (generic "you" - I don't like "one doesn't") don't like anything in a category, then simply don't vote. Voting "No Award" is malicious.
If nothing appeals to you, it doesn't mean it can't appeal to anyone and, really, you're saying, "I'd rather deprive someone and their fans of a Hugo award based on my taste than simply stand aside and let those who do like something decide it amongst themselves." It's nothing but spite. I don't know why the option ever existed (unless exactly for this when the fannish wars were about those commie weirdo Futurians or whatever) and, while I believe No Award has finished higher than some nominees, I don't think it's EVER been the top (non-)choice. Maybe once in the Nebulas, I can't remember; I doubt it. That might happen if there's an orchestrated campaign for it.
Really, there have been sub-par Hugo winners before (the Clifton/Riley novel is the standard example) but I doubt it much matters. On the other hand, can you imagine the "mainstream" lit snobs twisting it and making fun of a field that is so bad it can't even give awards to itself? Those NO AWARDs in the Hugo lists would be a far more obvious and permanent blight than just giving it to the best of your options on this slate, however non-optimal they may be. It would take "Hey, that was a weird year, they weren't very good" (except in Novel and Dramatic Short and several other categories where they may be as good or better than usual) and turn it into a "this was the year SF imploded" permanent scar.
I do not support a campaign of "no award," for reasons I've laid out
on my blog. But I also see no reason why I should reward:
(1) the efforts of two men to use a slate-voting mobilization scheme (which I already oppose on moral grounds) as a means of promoting themselves (to the tune of 11 nominations for person A's small press, 2 personal nominations for person A himself, and 6 (6!) nominations for person B.
From an ethical standpoint, that's obscene--even if you shelve, for the moment, any consideration of
slate voting qua slate voting OR the public statements of either individual, which are frequently (and dare I say deliberately) noxious.
[FTR I see this as completely different from some author saying "hey, here are the works I've produced this year that are eligible." In this case, persons A and B mobilized voters to make whatever political point they said they were making, but which
just so happened to also promote the interests of A and B.]
(2) works that are, simply put, not award-worthy.
Every year I use "no award" to separate those works I think would make worthy winners from those I think would not. And yes, sometimes I've voted "no award" above the actual winner.
Others are free to disagree and vote accordingly. But this is what "no award" exists for.