I used to do it like you stated. But I track a lot of books in spreadsheets to construct my reading lists, and one of the things that I've noticed is that the range of ratings on Goodreads is quite narrow. For instance, of the 381 books I'm tracking that were published in 2022, the Goodreads ratings range from a minimum of 3.14 to a maximum of 4.81. So there are only a range of 1.7 stars between the "very worst" book and the "very best" book. I think most people are giving books a 4, unless it was really good, and they bump it to 5, or it is meh, and they drop it to 3. This seems like a pretty lazy approach to rating books.

So now I have a rating system from 1 to 10 (which I divide by 2 to get a Goodreads rating), and multiple categories that I rate. For instance, I might really like the world building in a book, but think the dialog is crappy, or that the first two thirds of the book is excellent, but it fell short in the last third. People have a tendency to rate a book according to its worst attribute -"The book was excellent, but it had a weak ending, so the book is weak." Or, "the book was excellent, but the dialog was crap, so the book is crap". So I currently have seven categories that I rate, and average them to make a final rating. I have an overall informal rating as well, and if the numbers don't match the overall rating, I have to ask myself why the metrics don't match. Either I'm not being honest about it, or I'm missing a category.

In the end it doesn't matter, since most books add up to a 4 rating (out of 14 books read so far this year, one was rated 3, eleven were rated 4, and one was rated 5) . But at least I can explain my rating to myself.