I haven't read this book, but...

About 30% of negative word of mouth comes from people who never owned the product that they were talking about. If you’re a marketer, I’m sure this is pretty upsetting: you’re working hard on developing a product, and people are badmouthing it without giving it a chance. But consumers should be annoyed by this too because secondhand buzz is not very helpful. Word of mouth is a filtering mechanism that we use in order to find good products. In a society where every person recommends only products that they personally tried and liked, good products will quickly rise to the top. When people simply relay information that they heard, you get something that could be best described as a buzz bubble, as depicted in this review: “I haven’t read this book but judging from the online reviews below, I don’t think it’s a very good book” (one star). See slide show with some of these reviews here