I don't know much about web design, but what I know is that a page that is not polished is perceived like this by users, even if it is just a strange feeling that they can't explain.
That's kind of the point of the article though -- they're just getting by with the bare minimum, because they don't really care about the web. The consumer doesn't care, but a web company should care.
Hacker: "Oh my god, look at that 1px error" Avg user: "what a soft, easy looking webpage - did you see those images move on the front page?" :)