Providing readers with ratings is a hard thing to do. There are so many factors you can take into account – editing, language, style, comprehensives. You have to check how well book fits into most recent trends (especially nowadays, when each and every year new release of something appears on the market). Even though it’s hard to be fair using five scale score I prepared sort of the grading explanation. Hope this helps.

– extremely good

– very good

– good

– rather good

– fairly good

– fairly bad

– rather bad

– bad

– very bad

– extremely bad

– run for your lives!