This blog isn't so much about defining point of view but more about when and why. Also based on Becoming Your Own Critique Partner by Toombs and Walters.
We titled this chapter "Don't follow the Bouncing Heads. Part of the reason came from judging a contest when an aspiring author managed to get three points of views in one sentence and four in the paragraph. When an author choses a particular point of view they are showing what this character sees, thinks and feels. If shifting too frequently, the reader begins to feel like they have whiplash or are playing who's on first. We all know there is first person, I, second person, you, and third person, he/she. First person is both the easiest and the hardest to write. Easy because the writer can become the character. Hard because the I character tends to go off on tangents and to forget about the purpose of the story. Second person is seldom used in fiction but often in non-fiction. Most stories are done in third person and may be limited to a few characters or to step into the minds of many. The writer must decide what is right for the story they are telling.
Things to remember about changing POVs. Change when another character's vision is needed.. Allow enough time when changing to let the reader settle into a second person's shoes. Changing paragraph to paragraph and there comes the tennis ball volley. The length of the novel can also define how many characters heads the author is delving into. In a short work, too many POVs like too many cooks tend to spoil the action. Also make sure the POV character has a role to play in the story and isn't just a casual walk on.