IDK what platform that you are talking about.
I am on Streamate and how it works there is that after 90 days ratings do drop off if you have less than 4 ratings in a 90 day period you will go to the default 4 stars.
That is why that yeah I like the money but the first thing I always check for after a show is if they left a review. Over there just because they don't leave a public comment doesn't mean they don't leave a rating though. When they don't leave any rating at all, I am always a bit disappointed.
But then I did have one client send me a message saying that he found me on one of the affiliate sites and apparently they did not have a review option because he wanted to leave me one and wondered how he could do it. He did see me again though through the Streamate site and was able to leave one that way.