How so? Why would the most popular stuff always be the stuff worth reading? That's certainly not true for most media. Do you suppose that the Billboard Top 100 is the music most worth listening to?
Not saying that having an editor pick them out is necessarily going to do a better job, but there's certainly room to do a better job.
I think in a relatively niche community where the readership submits the content and then determines what's popular, ranking probably correlates better with quality vs billboard or other mass media where the relationship is strictly producer -> consumer. That's just my intuition though.
In any democratic system, the actual result of taking a vote will be a minimax of sorts: the result with the least aggregate distaste. This is why, if you have a non-niche demography for a vote, the top results will always be completely bland—no one can find a reason to dislike them, so the few people that do vote them up push them "all the way" up. Meanwhile, the contentious items—the ones that some love, and some hate—end up getting pulled down, because those who dislike it dislike it enough to overcome the friction of moving the mouse to the down-vote arrow and clicking (or to going out and putting out propaganda posters against that party, etc. etc.).
It would be a genuine invention, perhaps one of the only things worthy of an "algorithm patent", if someone were to come up with a way to encourage creative focus through the use of democracy. Imagine if "designed by committee" were actually a good thing!
As it stands, democratic voting systems are only useful as trained classification filters (i.e. spam filters where the "spam" is "stuff we don't like"). Actually ranking the "good" results should probably be left to editors.
Well, I agree, of course, it's hard to say that we don't do better than Billboard. That was a little bit of hyperbole. But consider: People upvote things for a zillion reasons.
Because it made them chuckle.
Because they agree with it.
Because it shoots down another submission they really disagree with.
Because the post wasn't very good but it had a link and the link was really good.
Because the author came and posted in the comment thread and said something interesting about it.
Because their buddy posted it.
Because a minor HN celebrity posted it.
Because it's all about banana-flavored threadsafe data structures in Erlang and they did their Ph.D. thesis on banana-flavored data structures and nobody ever posts about them anymore.
Most of those barely correlate to what we mean when we say "quality" at all. The people who upvote only things that are "high quality" probably upvote much less, in fact, than people who upvote for other reasons. So that's why I would not expect upvotes to correlate with quality.
At the moment, everyone upvotes anything containing the word 'iPad'. So boring. I think editorial control usually works far better than voting up/down by users. Democracy absolutely sucks.
There's a whole lot of "why I like/don't like the iPad" stories that seem to poke holes in your theory. Even in niche communities, the (relative) junk can worm its way to the top.
EDIT: Didn't notice axod's post deeper in the thread with the same point. Upvoted him.
Isn't that the point of upvoting?