> I'm wondering how so many reviews get written on a site like Amazon I'm sorry to burst your bubble. The well-respected consultancy User Interface Engineering has come up with the magic number of 1 review for every 1,300 purchases. "While only one in 1,300 purchasers of the product writes a review, the number who indicate a review was helpful is even fewer. For the Harry Potter volume, which is Amazon's best selling…
And I know that I for one usually don't upvote a review, even if I did find it helpful. I don't mean to be intentionally rude, I just somehow haven't gotten in the habit of doing that. So the number of votes on a review isn't an indication of the number of people who found the review helpful, but rather, the number of people who both found the review helpful and took the time to vote it up.
That said, yes, Amazon's immense customer base makes even tiny percentages of users contributing out to be useful. But they weren't always so large. I've heard that the main way they became the prominant online bookseller was precisely because they offered a review mechanism, at a time when other online bookstores did not, or offered a more feeble review system. Since it's so easy to add a nice review system to an online store today, that feature alone won't be enough anymore.