The following are some screenwriting fundamentals.
What I'd suggest you do is take a screenplay you've written that you feel is finished. Something that is ready to go out, then before you send it out - do some specific passes on the script focusing each pass on one or all of the following caveats that appear in far too many films...
1 - TRAVEL TIME.
Many screenwriters are guilty of this. Travel time is where we see the characters in transit, be it from the living room to the car outside, or on a plane from X country to Z country.
UNLESS we learn something of importance about the character - OR - there is a major story point to be expressed while the character is in transit - then - CUT ALL TRAVEL TIME.
There is nothing to be learned about watching a character walk up to a front door - hit the bell, wait the requisite period of time for it to be opened - then for the conversation to begin.
CUT straight to the conversation.
But even further than that - cut straight to the important part of the conversation.
Skip the pleasantries. I know it sounds obvious - but so many films have characters saying hello and asking how each other are before getting into WHY the conversation needs to take place in the first place.
That's the first pass I urge you to do. Go through and eliminate any travel time.
Go through and check that scenes aren't overt. I recently watched Hardcore Henry - which is literally a dramatisation of a first person shooter game. While it's entertaining in its own right - I can see why it failed to be a critical or box office success (okay, it did make $14m. but it could have made more).
It's too much like a computer game - the humour and acting are sub-par - the scenarios are ridiculously over the top. It's full of fan-boy teenage dreams - the super hot wife - the ubiquitous coke den with hookers... mass over-kill murder... chaos... impossible fight scenarios... this film (like it or hate it) is the epitome of OVER THE TOP.
The main reason this film didn't 'hit' as well as the hype suggested it would - is because of just how over the top it is.
I then watched DARK WAS THE NIGHT - and while this film is no perfect screenplay - the story is subtle. The dialogue is subtle - the emotion in the scenes is realistic because of the subtly.
Take a look at your screenplay - look at each scene - at the execution of each scene - and ask yourself - how extrovert is your writing of that scene. It is fist-in-face like Hardcore Henry? Or is it subtle like Dark Was The Night?
Rather than having each character SAY all their dialogue - can you have a character speak silently? What do I mean by that?
Watch season 4 - episode 13 of House Of Cards - a character asks Doug if he has been with someone in their final moments - as they die. He could have said yes, but it's waaaaay more powerful for him to stare quietly at the dashboard of his car. That's the same as saying yes, only it's more subtly - and consequently - more powerful.
Are you able to have a character ask a question without speaking? Can you get a character to simply look at another character - then for the second character to understand that a question is being asked? If so - go for this option. Subtly trumps over-the-top every time.
If you're worried you might lose your reader by only having your character look at the other character - you can write it: Jake looks to Michelle as though to ask (insert question here).
You've written the question so the reader knows what's being asked - and given the context of the scene your audience should understand the question being asked.
3) EMPATHY BEFORE FLAW
This is a simple one - but it's missed far too often.
Make me like your hero BEFORE you show me what's wrong with them. More often than not a hero's flaw is a negative. If you show me your hero in a negative light BEFORE you make me like them - my first impression of them will be - asshole - then it's a push up hill from there to get me to like them.
4) EMPATHY BEAT COUNT
Go through your screenplay - count how many scenes you have. Should be between 30 - 60. There's no magic number.
Then go through your screenplay and write down every time there is an EMPATHY BEAT for the hero. Break these empathy beats down into ACTIVE and PASSIVE.
You should know the difference - but just a quick re-cap - ACTIVE EMPATHY is when the hero DOES something we like them for. They save someone, they run after the mugger, they whistle blow on the bad guy etc....
PASSIVE EMPATHY is when something bad happens to them and we feel sorry for them.
How many ACTIVE empathy beats do you have in your film after the first act?
Empathy is not something that we setup in the opening 10 pages then forget about. Empathy is an ongoing thing. Think about real life. If one of your friends was a nice person 10 years ago, but they've now stopped being a nice person - do you still think of them as a good person?
The more empathy for your hero you have in your script the more the audience will connect with them.
There's no perfect ratio - but if your script has 40 scenes - try to get more than 15 active empathy beats for your hero. If you can make those beats happen ergonomically within the present storyline with only minor adjustments - your script will benefit greatly.
5) BIG GOALS AND MICRO GOALS
Okay - we all know that we need a major goal to drive the story. A film without a major goal will not work. But what you need are micro goals ALL THE WAY THROUGH.
Best way to test if you have micro goals is to look at each scene and ask - what is the scene objective here?
It's better if your hero is the one that has the scene objective - but if they don't have one - then there must be at least ONE other character in that scene that has a solid scene objective.
If there are no characters with scene objectives, then re-write that scene until there is at least one scene objective.
Take the example of Dark Was the Night - there's a lot of scenes where there's just a couple of characters talking.
Take the scene where the Sheriff is in the grocery store buying food. One of the town folk ask him about this monster they think is in town. He dismisses it, saying it's likely just a prank - then that same town fellow tells a story about how the native americans used to tell stories about a creature that lived up in the hills.
That's the scene.
What's the hero's (Sheriff's) scene objective? Buy some food? Talk to the town person?
Neither of those are goals toward the main goal. Neither of those are scene objectives. Then what's the scene objective of the town fellow? To tell his story about monsters?
That's not a scene objective. In fact, this scene has no concrete objective for any of the characters. This is why the scene falls flat on its face.
Now had the hero been after that particular town folk - as someone had said they'd seen him lurking around at night - then the Sheriff would have an ACTUAL scene objective - to find out the town fellow's whereabouts last night and to find out if he could have been the one that is responsible for the 'prank.'
While I'm on goals - I need to stress the importance of closed ended Vs open ended goals.
A closed ended goal is something broad and general like - fight evil.
A closed ended goal is something concrete - like - kill Darth Vader. It's something we can latch onto. There's nothing tangible about 'fight evil'.
Look at your screenplay and ask yourself what is the main goal? Is it open? Or closed?
Also - what are the scene objectives of each scene?