William Faulkner's story "A Rose for Emily" manages to maintain a level of suspense because the reader is not aware of Emily's insane behavior until the very end of the book when her long gray hair is found next to the skeleton of a man. Emily had evidently been sleeping next to his corpse/skeleton for many years.
If Faulkner had told the story from Emil'y point of view, it wouldn't have been much of a story because she most likely did not believe her reclusive manner or her strange behavior regarding the skeletal remains of her suitor.
In order to capture Emily's true nature, Faulkner decided to use an observant narrator. The story is told in first person, but actually uses the whole town's view point on Emily's behavior instead of just a single person's. The story seems as if it is told by the entire town rather than by a single narrator because of the use of phrases such as "we believed" when speaking of Emily.
Had Faulkner decided to use Emily's point of view, the story would never have been much of a story at all. Even if Emily did choose to tell the reader of her crazy antics, we still would not have known of the town's shock and horror when they finally unsealed the upper chamber and discovered her hair on the bed next to the skeleton.