Have you got the right protagonist?

Who is the protagonist of Frankenstein? Frankenstein the doctor or the nameless monster who is often given his creator's name?

It's hard to tell.

The novel follows the monster through his journey, but it's the doctor who needs to evolve. It's the doctor who needs to learn a lesson and to correct the mistake he created.

Maybe the more important question is: Why does it matter?

Well, your protagonist should be the heart of your story. They should be the person who has needs and wants that are driving the story. They should be the strong voice that helps drive the narration.

You're going to need to know who your protagonist is to pitch your story to an agent or publisher and to drive your story's heart.

Make sure that you are working around a protagonist, not just a main character.