>I wish more people understood that the goal of Stack Overflow is not "answer my question" but "let's collaboratively build an artifact that will benefit future coders". Perhaps SO could be doing more to educate people about this. -Jeff Atwood
But the way to built that knowledge base is by answering peoples questions because the questions people ask indicate what is relevant to answer.
Yeah, this is the kicker. I think SO's primary intended audience is people clicking Google search results.
If I'm Googling something technical and I see Stack Overflow/Stack Exchange results, I always click those first, because I know I'm almost always going to attain the most helpful-information-per-unit-time that way. Even if an answer's many years old, it's usually going to be more helpful than most of the much more recent links, which are often just cookie cutter blogspam.