What are we looking for when we open a book? A few things come to mind. Escapism, the need to run away from the harsh realities of life. Entertainment, the need to escape boredom. But also knowledge, voyeurism, empathy, or creativity. We don't read for the same reasons, but we all read because we are looking for something. Anything.
All great books have one thing in common though: they are actionable. They inspire the reader to act or react. Whether we read a love story or a philosophical essay, we want to be forced into a primal eruption of feelings. As Paulo Coelho proposes, a great book is a catalyst.
This is what makes powerful words.
This is also why writers should create to scratch their own itch. Albert Camus's Myth of Sisyphus is a great example. It's not the clearest book. Some paragraphs are hard to read and some ideas hard to follow. And yet, it's a book asking great questions and providing great answers that contributed to his obtention of the Nobel Prize in Literature in 1957.
If there is one thing I learned from reading, it's that there's no definite recipe for writing success: only trials and errors to learn from, and the secret sauce called actionability.