A hugely important part of creating a successful film is to avoid cliche. It sounds like a no brainer - but you'd be surprised how many people think they've come up with a great new idea when really they're rehashing the same old same old that's been done a hundred times before.
When you condense your concept into a single sentence how does it sound? Does it sound fresh and new? Does it sound like nothing anyone has seen before? Or does it sound like just another film that's not terribly inspiring?
Your quest to create something new doesn't mean you should create the wackiest, weirdest storyline you can imagine. Different for the sake of being different is just as bad as cliche. You want your story to be relatable, you want your story to be intriguing and understandable.
If you write a story about a lady who is terrified of bricks you're going to have a hard time finding an audience who can relate to that. Write a story about a lady overcoming an oppressive family that doesn't want her to go out on her own and live her own life and you've got a much larger audience.
Successful films are a delicate combination of the new and the familiar. It's a fine balance. Too much NEW and your story will be too strange and oddball to find an audience. Too FAMILIAR and it will feel stale and unoriginal.
Objectivity is an important thing. Create your idea - then test it out on people. Choose a wide range of people and here's a great trick - don't tell them that YOU created the idea. Either tell them that you read about this film online and want to know what they think of the idea. Or say you over heard someone talking about this movie idea.
When you tell people you know about an idea and they know that you created it they're not going to give you an honest opinion.
How ever honest you think your friends are - they're just not that honest. Even that friend who prides themselves on being the blunt and honest friend will not give you an honest opinion on your story concept.
If you want an honest opinion spend a year writing your script then send it to a screenplay competition, see how far you get. Send it off to a dozen producers - waste their time and see how many responses you get back.
Friends and family are a great place to start with pitching a concept - everyone sees films and everyone has an opinion.
You might be thinking - but I don't care what they think, they don't know anything about films - you couldn't be more wrong if you tried. They don't have to know about the technical side of film to have an opinion on them. Each and every one of your friends and family are part of the VOTING MOVIE PUBLIC.
What do I mean by that - just like voting at an election - everyone gets a vote in the world of movies. Every time ANYONE buys a movie ticket they're voting for a style and genre of film. The more people who vote for certain types of films the more likely that type of film will have more of it made.
So when you're sitting there staring at what films are getting made and you can't understand WHY they don't make 'good' films - you need to reconsider your position. It simply means there's more people out there that would rather watch films that are different in style and taste to the films that you want to watch.
Here's the second huge tip of the day when it comes to concepts - don't write for yourself.
Write for the largest possible audience there is.
Maybe you hate stories that are grounded in music. But when you check your ego at the door and look into it - stories that are grounded in music have a HUGE audience base. In general, people love musicals and they love stories grounded in music.
Perhaps your don't like horror films - can't stand them. Thats' a shame - because there are millions of people out there who LOVE them.
When setting out to make a successful film - think outside your comfort zone. Look into genres and styles of stories that are hugely successful, don't just write what you want to see - write what the movie going public wants to see.