The star ratings system was something I spent a long time on researching, prior to launching Book Notification.
First, a universal ratings system in regard to books is tricky. Everyone defines theirs differently. I spoke to many people prior to launching the site. Some only give a book 5 out of 5 if they would ever re-read it. Others rate any books they like as 5 out of 5, and any they don’t like as 1 out of 5, with no in-between. Everyone has different feelings on it.
But the one consistency I saw that was that many people felt a 5 star system was just too limiting. People were complaining a lot about wanting a half star system etc, especially as all book sites display ratings with decimal points as opposed to absolute numbers. People felt handcuffed by the 5 star system, especially when it comes to rating books either 3 or 4 stars.
So that’s why I came up with the 10 point system instead. It allows people who were feeling handcuffed by the system to be able to have more flexibility with their ratings if they choose. But people don’t have to use that if they don’t want to. Want to stick with the 5 star system? Any 5 star book is a 10 on Book Notification. Any 4 star book is an 8 on Book Notification etc. Our Goodreads import system converts them automatically.
If you choose not to read any book rated below 4 stars, then with our system you would choose not to read any book rated below 8 stars.
Also as I do want to accommodate all users and their preferences, we have on our to do list at some point to incorporate the option to only see 5 star ratings. We would still use our 10 star system, but if you toggle that option, from your perspective, you would only see book ratings scaled by 5 stars.