We can all imagine a triangle: three lines, three points, three angles. And the image of a triangle is a great way to think about the writing process. There are always three parts: the writer, the material, and the audience.
But often writers are guilty of a linear execution of their work. When a writer is only concerned with the material, there is always the potential for fatal flaws in the storytelling to occur.
Imagine drawing a horizontal line between the writer and the subject, or story material. The relationship is very direct, and intense, and simple, but very often the final product is written to only one person: the writer him/herself.
There are always three parts. In screenwriting the writer must consider his/her relationship with the script as well as explore how the script will affect his/her audience. Simply put, the writer writes for an audience; therefore, the decisions he/she makes when presenting the story are influenced by how he/she wants the audience to feel.
Does the writer want the audience to be surprised by the unexpected, or smart by allowing them to connect the dots? Sometimes the writer wants the audience to discover along with the character, sometimes we learn before the character, and sometimes we are the last to find out.
It’s impossible to make reasonable decisions if the writer is not focused on the complete triangle: writer, story, and audience.