I think the following two main reasons caused Google Answers' failure: 1. Their business model was too strict. The price should be $2-200 per question. I think if they can allow 1 or even zero (which means free), more people would like to try it. 2. Google Answers is not true Web 2.0. Only 250/500 search experts can answer (and lock the question). No opportunity is given to general users and other experts. So there is no real competition. Maybe many general users can provide better answers these experts.