Dark Mirrors: A Story of Alien Invasion by John Walters gives a glimpse into a young girl's choice in prison, during a war the humans are losing. Based on the description, I thought this story would be more focused on Bethany. However, the author spends most of the story describing everything from the POV of Margaret, a military officer of some importance. By the time readers learn anything about Bethany, the story is over, with a rather abrupt ending. After making such a big deal about the nature of the war, the ending felt unresolved...incomplete.
I try so very hard to go into a story without any expectations, aside from wanting my imagination fed. Sometimes a story leaves me wanting more because I enjoyed it so much. More often than not, a story leaves me wanting more because the author only fed me scraps of information.
I'm often reminded of something an English professor told me, "Don't introduce a gun into your story, unless the gun is going to be used at some point." It drives me crazy when an author includes unnecessary details, but refuses to reveal more about key details, giving readers tidbits of information resembling a breadcrumb trail leading to nowhere.