Some things go unnoticed when they work. Leadership, for example. You only ever see the bad type. Typography is another. When the font is right, you won’t even remember which one it was. Non-fiction writing enters this category too.
Writing is unique in that you are creating a world, but you are also making the window through which readers will see that world. And in non-fiction, you want readers to fully take in what you are showing them. Choppy prose is a stain on the glass; it attracts attention to itself. The purpose of a window is to let the light in. So let the light of your world shine through.
What does it mean to let the light in? It means that the reader does not notice that they are reading. Your readers should not have to decode your text to get to the idea, they should get to the idea immediately. When writing, you are planting information into the reader’s brain. Do not plant the words, plant the concept directly. Hard to do when you are literally writing words, but that is the challenge.
How does one accomplish this? Write as simply as you can, without compromising on your ideas. If the passage is hard to understand, reduce. Express the same message with fewer and simpler words. It sounds easy, but it is not. Why? Two things.
First, a painter will always start with a blank canvas. Over time he will add more and more brushstrokes, until the piece is done. It is a cumulative process, where the painter starts with nothing and ends up with the maximum possible number of strokes on canvas. Even when they make mistakes, they almost always cover them up with more paint.
We see the intuitiveness of creating something visual like painting, so we think it must apply to other creative forms too. Most, when they see a passage that was not clear in their first draft, add more words around it in an effort to clarify it. This is unlikely to be the right approach.
Second, our formal education conditions us. High school tells us that complex is good. In academia, entire departments are based upon the premise of making the glass as opaque as possible. For example, Jonathan Bennett has been paraphrasing, modernizing, and simplifying texts by early modern philosophers so that more people can access them. Philosophy teachers’ response has been “uniformly negative and sometimes hostile.”
Understand that writing is not a linear affair. If you find yourself deleting rather than adding, you are probably on the right path. Unlearn what your formal education taught you, and do not let opaque texts fool you. Most of the time, there is nothing behind the smoke.
P.S.: Some are afraid that by writing plainly, they will be boring. Plain and simple does not mean styleless. There are a billion different ways to write simply, be it through word choice, punctuation, or flow. Your voice will shine through.