We’ve all heard of the rules of thirds but have you heard of the rule of three?
The rule of three is a writing principle that suggests that a trio of events or characters is more humorous, satisfying, or effective than other numbers in [the] execution of the story and engaging the reader. The reader or audience of this form of text is also thereby more likely to remember the information conveyed. This is because having three entities combines both brevity and rhythm with having the smallest amount of information to create a pattern. It makes the author or speaker appear knowledgeable while being both simple and catchy.Wikipedia
Although a writing principle, one of my photography instructors, Loren Fisher, has suggested using this principle when composing images with more than one object of focus.
I’ve been trying to use this principle in my images.