PIXAR’S 22 RULES OF STORY (RULE #2)

RULE #2: Keep in mind what’s interesting to you as an audience, not what’s fun to do as a writer. They can be very different. 
This may seem like strange advice at first blush. If something is interesting to you as an audience, shouldn’t it also be fun to write?  
Seriously; I’m not being flip. Storytellers should enjoy writing things that they enjoy reading and viewing.  
If that’s not enjoyable to you, maybe storyteller is the wrong calling for you. Every story needs to flow from a place of joy, passion, love, or yearning within the storyteller, or it certainly will not be fun to write, or to read.  
The premise of the statement really stems from the common notion that writers in particular naturally enjoy writing internal monologue, evocatively meandering descriptions, abstraction, and other things that “shouldn’t” be in a screenplay.  

This advice was clearly given to Emma by someone who adheres to that common notion that all writers prefer writing things that ought not to be in film blueprints, which isn’t true. Many writers completely enjoy writing action, concise description, and external, subtextual dialog.  
But what should be in a script depends on the target audience of the screenplay – meaning the audience who will read the script, not who will see the finished film.  
If you are writing a spec that you’re hoping will sell or get you a job, don’t do any of those “writerly” things like write novelistic description or rely on internal monologues to carry the story (or, at least, use them very sparingly).  
If it’s a work-for-hire, do whatever the person who hired you asked for (in Hollywood, that’s generally not to fill the script with internal thoughts and meandering descriptions – but the producer or director may ask for exceptions to that rule).
If you’re writing a no/lo-budget script you’re going to shoot yourself, you may do more of those things — so long as you have a clear idea of how they’re going to get on- screen. If you can’t visualize it (or speak it aloud), you can’t shoot it. 
A common example of a “writerly mistake” that elicits this advice is to load “a look” with a lot of subtext. For example:  
"He looked at her as if to say: ‘how can you think that about me after all these years?’" 
A look can only say so much, so you’ll need to limit what you try to say with it to things actors can actually convey in a look or action. Which is a lot less than might hope (no affront to actors intended, they can say a lot more with a look than the rest of us). Otherwise, put it into action or dialogue subtext. 
If you’re excited about the idea of a quiet character who generally “lives in her head”, either do the “bad” thing and use voice over, get very creative about expressing that through action and subtext, or write a novel. 
As for extensive descriptions and abstract ideas about theme, quite often Directors who are writing for themselves will put those things into at least one draft of the script.  Since they’re visually designing the film as they write it, they know how they want to visualize even the abstract ideas (perhaps implying it with an effect, camera angle, filter or color treatment).   
You can’t usually get away with extensive description or abstract thematic notes in a spec, or even a work-for-hire script, but plenty of people do it for themselves. If you’re writing for yourself, you can too. (Though generally it gets taken out of drafts that go to actors.) 
But always keep in mind:  
Film is a visual medium.  
Ultimately a screenwriter is trying to convey to the entire cast and crew the basics of how the film will be staged and shot, not just the character dialog and emotions. Anyone who thinks otherwise is in the wrong business. 
There’s also the aspect of the rule statement which comes from the assumption that because writers find certain aspects of writing more fun, they prefer writing things that are structured for other media than film.  
Watching a film, even the funky experimental stuff, is a different experience than reading. And commercial films have a certain three act structure that is expected to underlie the narrative. You need to meet those expectations. 
The less filmic the writing, the less filmic the audience experience will be when it’s translated to screen. Whether that’s a good or bad thing is debated endlessly. Ultimately that’s a matter of style, tone, and material versus return- on-investment considerations, and cast and crew capabilities.  
Making a “no-budget” experimental film (or something for a government film board)? Do any crazy thing you want. Anything. Those kinds of films are playgrounds and laboratories for wild ideas, and sometimes those experiments even result in something amazing.  
Otherwise, if the goal is to write a script that will attract a Hollywood cast and crew, get prodco and studio backing, and find a general film audience — write a film.  
That means stick to film structure and pacing, and write concisely and visually. 
Finally, perhaps what the statement is trying to get at is: don’t be self-indulgent. To avoid being self-indulgent, simply think about an audience that isn’t you. 
You have to enjoy storytelling to a broader audience than the one inside your skull, or film is the wrong medium for you. Film*making* is the most collaborative art / entertainment process that exists, and film *viewing* is a global shared experience.  
That doesn’t mean you bring nothing of yourself to screenwriting, of course. All stories come from inside the storyteller. 
But when writing screenplays you do need to be cognizant that you’re just making a blueprint for a series of
collaborative, shared experiences — not an isolated recounting of your internal thoughts.  
As a writer, I love isolated recounting of internal thoughts. A lot. I just don’t think a screenplay is (usually) the right place to put them.  
Ultimately, I believe that the subtext of rule #2 is all these things:  
• Write something that is structured like a film, not some other medium. • Write for an audience that exists outside your head • Write visually.  • Do these things because a screenplay is just a blueprint for a film, write a blueprint for a film, not a finished product that is intended primarily to be read. 
If you’re writing screenplays, the reason is almost certainly because you love films.  
So when writing them put yourself into your film audience mindset, and have fun doing those things. Get into it, and enjoy it, and it will make your film writing better.  
At least this will make your commercial screenplays in the Hollywood mold better (which, let’s be honest with ourselves, includes the majority of “Indie” films as well).