Sparkatale

Personally, I think that prologues are an iffy business but depending on their content, they can be phenomenal additions to your novel. Here is my list of pros and cons based on my opinions and research:

Pros:

1. They can hook the Reader. (This has a con to it.)
2. (When done well) they can be useful for introducing previous conflict that just can NOT be introduced at the beginning of your story without being too much of an info-dump in the middle of your character's story set up. (This has a con to it.)​
3. Can give a dramatic peek into the end. (This has a con to it.)
4. If done should be used to raise questions about the characters. If you are using it to present previous conflict there should be a little bit about your main character so that the Reader asks, 'What does this massive war have to do with Cinderella?' 'Is Flounder one of these mystical half werewolf half fae descendants?' or 'How will Mushu react when he finds out Mufasa just came back from the dead?'

Cons:

1. Prologues typically include unnecessary back story, or back story that can be saved for a bigger reveal later.
2. When in a different tense or POV, a prologue can distract from the actual story by disrupting the flow of the story or giving the Reader something trivial to focus on. If this happens they can spend too much time trying to find clues that support or explain what is happening in your prologue rather than paying attention to other key tidbits that are important to your main story.
3. Because of how they are so unimportant most of the time, many editors/publishers won't touch a book if they see it has one.
4. They can be info-dumps which are a big no-no at any time. (This has a pro to it.)
5. If you use it as a dramatic peek into the end of your story it can come off as a cliché. Especially since it was used by Stephanie Meyer in her Twilight saga. Because there are such strong opinions about this series this could be both a good and bad thing but in light of the Fifty Shades of Grey (E.L. James) commotion on social media more bad will come than good.
6. They often don't even make sense till the whole book is over and at that point the reader is (hopefully) so enthralled with the ending and the plot that they aren't going to be concerned with the fuzzy beginning they don't even remember. (This has a pro to it.)

[Quotable - Louis L'Amour - Writers Write Creative Blog]

Check out this link in which blogger Kristen A. Kieffer discusses the Do's and Don'ts of Prologues:

http://www.shesnovel.com/great-prologue-debate-dos-do-nots/

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