A writer must not shift your point of view.

I’m a big fan of this one! I know there are popular (VERY popular) writers who shift POV within scenes, within paragraph, sometimes within sentences. For the life of me, though, I can’t figure out how to read those writers.

I have to use clean POV for my own sanity. If I’m in Mary’s head, there has to be a break before I hop over to Jane’s head. It can be a new scene. Or it can be the same scene repeated from an alternate POV. I kind of like to do those when I can manage them.