There is a different reason as well, most of these stores highlights reviews of 1 and 5 star. Some people (well I guess all people that leave reviews) like to be highlighted, so they only leave 5 or 1 star reviews. This was a pain when I was managing a Google app and part of the performance review was the average rating. This was a small app with few reviews so the jokers that liked the app but left 1 star review to be highlighted really made a negative difference.

Just to be clear, I was OK with users leaving 1 star if they didn't like it or even better had some constructive feedback. But many were like "great app": 1 star, or "Hi single guy here, and ladies around?": 1 star.

If you force users to provide feedback, even if optional, expect many invalid results

In my experience, users won’t go out of their way to leave a worthless review. So if your app doesn’t nag, you have less spam. But that also means you miss a lot of legitimate people who don’t have the time or knowledge to leave good reviews.

Gift and curse etc

> If you force users to provide feedback, even if optional, expect many invalid results

I understand what you mean, but the phrasing of "forcing" someone to optionally do something is odd.

A pop up is forcing users to acknowledge rating the app. It’s not truly optional when you get spammed once a day to submit a rating. So you get angry people submitting unhelpful ratings because they don’t understand the UX

There was no nagging, never asked the user to leave a review. They really used it as a dating service all on their own.