I think many, if not most, book/graphic novel to movie adaptations fail because movies by definition are much simpler than books. Let's assume the average movie is 90 minutes long. That's not a lot of time to develop a handful of characters, convince the audience to invest emotionally in them, and then lay out a meaningful conflict the characters must resolve. Whereas a book has the advantage of a narrator, that is to say, having insight to a character's thoughts means the reader has a much easier time connecting to him/her or at the least can empathize with his/her motivation. This means a well written book can do what a movie can't in about 150-200 pages. I can however think of a handful of good adaptations that were good solely because they digressed so much from the original material that the movie simply became incomparable to the source. In that case, the movie must be judged on its own merits. Focus: Talk about a good book/graphic novel to movie adaptation. Did the movie maintain the same basic story/elements or did it digress enough that the source material became irrelevant to a conversation of review? Bonus Focus: Which movie adaptations ended up being better than the source material? Anti-Focus: Which movie adaptations ended up being far worse than the source material?