So, be honest in what you say and only write reviews if you personally bought or used the reviewed product or service. For example, Google offers clear guidelines on the type of content that can be published in its reviews, and so does Amazon regarding its customer reviews. Typically, you need to sign up on a review platform and fill out the offered feedback form to leave a review. Why do we need good customer reviews? Customer reviews often highlight areas where the product or service can be improved.