Why is the app not being reviewed?

Question

Apple App Store

I downloaded the app and asked a friend to try and leave a review. He downloaded the application, launched it and wrote a review, but neither the rating nor the review was displayed in the app store, not in the comments section in the app store connection.
Tell me, is there any algorithm for which reviews are published and which are not? Maybe the review is only shown to those who have launched the app a certain number of times or used it for a certain amount of time. If you can tell me where I can read about it, I will only be glad. Thank you.