I always groan when I hear someone say he has great idea for a screenplay, or a sitcom, or a book or anything else that can be written for that matter.
You don't need a great idea or even a good idea as long as the script itself is somewhere between good and great (inclusive). You can write a sitcom about NOTHING, make a ton of money from it while it's running and then sell the syndication rights for $1000,000,000.
That's right - a billion dollars.
If you don't believe me, ask Jerry Seinfeld and Larry David.
Ah, now I know what you're thinking: if you can make $1 billion from writing about nothing, how much more can you make from writing about something really fascinating?
It's a fair point but it means you're a seriously greedy bastard.