3 ms·

Question and answer sites usually fall in this category (irony of this being on Quora is not lost on anyone)

• jdp23 15y ago
  Naver, yahoo answers, answers.com, and stackoverflow are counterexamples. You're right though that there are a lot of failures
  • hasenj 15y ago
    I would classify yahoo answers as mostly a failure.
    • jdp23 15y ago
      Really? It's been a top-30 web site for four or five years ... Why do you see it as a failure?