There are symptoms that can be identified if you know what to look for, and they usually give a pretty good indication of what the problem is, whether the script is slow and heavy, or too long, or all the characters sound the same. If that’s the case, then how do you fix it, or shape it, transform it from a “bad read” into a “good read”?
For example, if your dramatic premise seems weak and not clearly articulated and defined within the first ten pages, then the chances are that the Set-Up is weak and the material is going to wander around in different directions and lack a dramatic focus. That’s a symptom; let it go on too long and you’ve got a dull screenplay; just as a scratchy irritation in the throat is sometimes the symptom of a cold or flu. Symptoms reveal things, and in the “art” of medicine, if you read the symptoms correctly, then you can find the cause, and heal the disease, whatever it might be. At least, in theory.
In screenwriting you cure the problem by knowing and understanding its symptoms. For example, suppose a writer wants to create a strong action line and, in so doing, sets up the story so fast, he or she simply skims over, or omits, necessary and essential character information? It won’t take the writer long to realize the character’s been sacrificed for action.
We can identify this because the character will be so busy reacting to the events or the situation that we don’t have an opportunity to learn anything about him or her. That’s a symptom. And it always seems to lead to a dull and boring read. When I see a script unfolding like this, with the character simply reacting to his or her situation, I’ll give the writer thirty pages to see whether it works or not. If it doesn’t, I’ll stop read