Five-star ranking systems are popular among book readers. But what does a star mean? That you like a book? Through a year, how can you be sure that the two-stars you gave in January means the same as two-stars in July?
So, thinking about topic expertise and quality of writing, let's set out stars we can stick with.
★ How did I reach the end: Somehow the author found a publisher who overlooked their ignorance of the subject, and an editor who helped them string together sentences. At least they can spell.
★★ My mum said if you have nothing nice to say: Well, the author does sound like they know what they're talking about and can talk well. Albeit in a monotone.
★★★ Worth the time: Now you've got a decent chance of learning something new from an experienced researcher whose writing gets out of the way. Standard issue.
★★★★ Tell your friends: You're reading an expert in the field with something intelligent and original to say, who can explain it to the layman. Confidently recommend it.
★★★★★ Make room on your shelf: An outstanding book that challenges your thinking with memorable writing. Buy the hardcover and never let it go.
On occasion, you may be permitted to give a bonus star.