Curious things, habits. People themselves never knew they had them. [Witness for the Prosecution, also published in The Hound of Death and Other Stories.]
I set myself up for a lot of trouble by wanting to tell a story that is fairly earnest and emotional and expressive, but to do it in the most subtle, realistic way.
Humans know when it's not a good story. Unless you do this for a living, you may not know exactly why you don't like a story, but you can't fool an audience ever. They know when you have it and they know when you don't.