I recently read a short story where out of the blue and with no warning, the main character dropped dead, stopping the story cold. Though it was intended to be a surprise ending with an ironic, poignant twist, it felt more like a cheap shot — plain old shock value for shock’s sake.
The problem with shock endings is that there’s no second act for the author. No sequels for the director either. Think The Sixth Sense. M. Night Shyamalan hasn’t produced anything of similar stature since, unless you count those Amex commercials.
Once the reader knows an author is out to trick them, because that’s their shtick, it’s like approaching a street huckster. Even for those that want to be suckered again, it’s nearly impossible as a writer to meet the raised expectations.
If you want to tell a ghost story, then let the reader in early. Everyone sitting around the campfire knows the stories are meant to scare the bejesus out of you, but that doesn’t lessen the entertainment value. And, there’s nothing wrong with an ironic twist, like “The Gift of the Magi”, or “The Necklace”. A surprise ending works when it’s subtle and leaves the reader with an ‘ah ha’ moment, not whiplash.
Readers need a thread to follow from beginning to end, one they can trace back with appreciation. A slap upside the head as an ending is not the same thing, and will normally be tolerated only once.