Can you write some more context? What kind of reviews?

You can become aware of the downsides of your work, and they give people a good preview of what you do/ your app does. They can also be a good motivation.

For SaaS businesses G2 and Capterra are critical acquisition channels, and those are driven by the number of reviews you harvest.

- Review can be a double edge sword, on my last product there are some users that were fanatics to our product and they write reviews then we got a user drop in just half an hour. - Review can be a key point to bringing user trust - Review can be the best way to help you define the feature/update