Communicating your story effectively to your audience is one of the most important things you must do as a filmmaker. This can be accomplished while writing the script and shooting, but most of the final decision making for the story is done in the editing room.
How do people learn?
Understanding how people an "learn" your story and how they learn from your story is critical for an editor. Some people learn from hearing, while some learn from reading and some from doing. While an editor can't have his or her audience do actions, they can show them how things are done.
Most people learn from a combination of these things.
To use these insights practically, while editing you should always consider how the audience might understand the information you are presenting that will further them into the story.