There are no hard and fast rules in writing.
For a lot of folks, their first introduction to writing instruction comes in the form of entry-level writing courses in high school and college. These courses are tailored toward the lowest common denominator: usually, people who have little to no writing experience, and are not necessarily avid readers. They also mostly focus on essaying and critical writing, rather than creative writing.
Many writing skills, especially style and voice, are learned through experience in both reading and writing. These beginning writing courses are not comprehensive enough to go into those subjects in great depth. Instead, they teach many hard and fast rules designed to help new writers avoid common pitfalls.
Here are a few:
Use an active voice, including sentence structure and verbs.
If you can use fewer words, less is better.
Because of this first exposure to writing instruction, many writers never move past that very basic, simplified way of thinking.
Many things only work under skilled application, but pretty much everything has a place among the countless variations of genre, voice, and narrative styles. Being able to tell where and how these tricky elements work is one of those skills of experience. But think of these things as a “forest for the trees” sort of issue… don’t get so caught up in the rules, that you forget the point of it all.