I forget where I first heard it, but there's a joke about two economists walking down the street. One of them notices a $20 bill on the ground and points it out out, saying "Look, it's $20 just lying there on the sidewalk!" The other shakes his head and says "No, that can't be true; if it were, someone else would have picked it up already"
HN equivalent: someone sees a link to an article and says "why would I read it, when all relevant information has already been incorporated into the comments?" Its the "efficient comments" hypothesis, all information relevant to a rational HN user about the article is already in the comments.
