Every story has already been told

When I first started writing there was a phrase I refused to believe.

'Every story has already been told'

The more I write the more I'm convinced that it's true. For the most I honestly can't remember the last thing In watched that has at it's basis a unique plot. There do exist ways of presenting writing that has never been done, but if you consider only plot, then it's been done before. In fact one book I read on screenwriting broke plots within the discipline down to three points: incident, escalation and resolution. When you begin the apply that to writing it does appear to be true.

For example:

Avengers Assemble
Incident = Tessaract is stolen
Escalation = Loki attacks S.H.I.E.L.D and the avengers
Resolution = a grand battle in which Iron Man risks all to save the day.

It is entirely possible to add more points, but essentially the point holds. Even an epic movie can be broken down to three simple points. It brings to mind the storytelling module I did at University. The tutor told us that all stories can be broken down into 'nodal plot points'. By doing that you only have to remember a few things and then improvise around those points rather than learn an entire story word for word. Even long pieces of literature can be broken down in the same way.

The Lord of The Rings
Incident = The evil Sauron's weapon is discovered.
Escalation = The 'goodies' set off to destroy the weapon plunging the world into war.
Resolution = The 'goodies' destroy the weapon thereby killing Sauron and saving the world.

The Divine Comedy
Incident = Protagonist is sent to hell to teach him a spiritual lesson.
Escalation = Before the protagonist can return home he must journey through purgatory.
Resolution = The protagonist arrives in paradise and learns that there is hope for his soul yet.

If it is true that every story has been told then why is it that writers continue to write. The answer is actually quite simple. Character. We as readers, viewers or audience are drawn in by interesting characters. We fall in love with characters. We are willing to learn about them and eventually we begin to root for them, or hate them and hope that they experience their downfall.

How else is it possible for 'reality' TV (the quotation marks are because it's folly to believe that what we see on TV is, in fact, real in any way) to become popular? How is it that a poorly written book, that destroys one of the most cool and popular monsters in mythology (twilight), becomes popular? People evidentially begin to care about the characters. They want to know what happens next.