We know things about stories. They begin "Once upon a time" and end "They lived happily ever after."
Except, well, when they don't. Except for when there's a whole second act beyond "happily ever after."
I recently read a draft of a story for a friend. She started the story, she said, with the aim of finally writing something with a happy ending. But when she was finished, that wasn't what she had. Except, the ending that she had was perfect. Well-paced, all the needful emotional beats hit, and something even better than a happy ending: an ending with potential.
It made me think about what I want when I read. Oh, I have my comfort books, romances mostly, that are the literary equivalents of a cup of hot chocolate. I love those books, and they fill a need for me.
But the books that really resonate in my soul are the ones where the ending is right, rather than necessarily happy. And that's actually, I think, a much harder trick to pull off. Because the good guys don't always win, and even when they do, not everyone survives to see it. Hearts get broken, and foul deeds go unpunished. A wizard may choose to break his staff and drown his books, and there is a truth there that is deeper than the fleeting pleasure of happiness.