Thesis Statement = character want

Your character's want and reason for that want are the thesis statement of your story.

In an essay's first paragraph you make a point.  You put forth an argument.

In the first scene of your story, your character should make an attempt and explain what they want.

In each scene after that, there should be a thesis.  A scene objective.  An attempt toward the reaching the story objective.

The thesis statement should remain flexible until the paper is actually finished. It ought to be one of the last things that we fuss with in the rewriting process

The above quote rings true when it comes to stories.  If you change the story want, you change the story.