When it comes to memoirs/autobios, I tend to rate them on how much they share about their lives. When it comes to historic events, I will give high ratings if the author clearly did a lot of research and digging on a topic where information is not readily available. I can appreciate an easy to follow book and also a very scholarly one as well. I read a lot of different kinds of books, I will give high ratings for authors who hold my attention to the point where I’m not reading other books in between (which is often).