From experience, I can say that sometimes a story suffers from uncooperative characters. You begin building your plot from exposition up, placing your carefully crafted characters in situations that they were designed for. It should be perfect. But characters don't always take the road that you lay out before them. It's usually your fault-- you gave them specific personalities and whims, and changing them mid-story to fit your plotline is difficult. When you bash them into different people, the story suffers tremendously.
That was my problem with Her Fearful Symmetry by Audrey Niffenegger. She sets up these interesting characters-- two subtly warring twins, an amature ghost, an OCD crossword architect-- then seems panic when their personalities battle with the story. Niffenegger's story is unique, so the contention can be sad to watch. After their estranged Aunt Elspeth dies, mirror twins Julie and Valentina move into her cemetary-side apartment in London and gradually adjust to independence from their parents and each other. They are not alone, however-- Elspeth still haunts the apartment, watching as her two relatives live her life while she floats in limbo.
It's an intriguing storyline, but the characters don't fit the actions that Niffenegger sets out for them. After interacting with the ghostly Elspeth, one twin is warned out of nowhere by her aunt's beau that Elspeth always has an ulterior motive, that she really doesn't have her niece's best interests in mind. This pronouncement doesn't fit with anything that Elspeth has demonstrated so far in the story, yet it foreshadows later events. The OCD crossword puzzle master manages to drive his wife of 25 years away, yet blithely accepts medication from his brand new neighbor girl. It seems like Niffenegger had a goal that the character keep obstructing with traits that she designed, so she shoulder-checks them out of the way for the sake of a pre-planned ending.
I find it strangely upsetting that these characters and the story can't seem to get along. I really want to love this book for the dark, slightly unnerving theme of the transient nature of self, but I can't get over the actions that the characters are supposed to take. I'll end up reading the book again for the descriptions and occasional chills, but it will never be truly great in my eyes.