Amazon calculates a product's star ratings based on a machine learned model instead of a raw data average. The model takes into account factors including the age of a rating, whether the ratings are from verified purchasers and factors that establish reviewer trustworthiness.
Everything in this book are just unrelated statements. These are not steps. These are independent set of statements to address the situation mentioned. But it none of them is certain to give a desired outcome. One of the most useless book!