If you read a lot of book reviews (I do for fun), people in general tend to rate the first book in a series better than its sequels. However, they usually aren't specific with their reasons. What things make a sequel less entertaining than the original book? Is it because the main idea isn't so fresh anymore? Do elaborate. Here are my pet peeves: 1 - The series starts out on one note and then deviates. The X-Files starts out with two FBI agents investigating bizarre occurrences in order to prove (disprove, in Scully's case) the existence of the paranormal. [I know that the X-Files is a TV show, not a book series, but it is the best example I could think of on short notice.] Not only do Scully and Mulder never really get any proof of the paranormal in the mainstream (except for the fluke-man, most of their hard work is immediately covered up by their superiors, yet they keep on going without trying anything new like taking cameras with them and sharing their discoveries first with the newspaper and then with their bosses), the show suddenly gets all bombastic, with prophecies, a miracle birth, and an upcoming mega-threat to human civilization. It's annoying when a series that started out interesting and new begins drawing too heavily on old formulaic mythology to the detriment of its original premise. 2 - Too many main characters die in order for the author to achieve a "sufficiently dark atmosphere." This is just plain depressing. When Sirius Black, my favorite Harry Potter character, died, the pleasure of the series also died for me. Lord of the Rings got along just fine with none of the main characters getting killed for good, and the sense of peril was in no way diminished.