“The writer turns in a script. The producers and studio executives read it, give the writer their ‘development’ notes, and he goes back and rewrites as best he can, trying to make everyone happy. If it comes back and it’s great, the studio and the producers will try and attach a director and stars (if they haven’t already), and hopefully the picture will get made.”
The producer or studio executive, too busy/bored/illiterate to read the script for themselves, sends out for ‘script coverage’ — advice on the potential of the script from a professional script reader.
“Everybody gives writers notes,” says screenwriter Richard Friedenberg (Dying Young, A River Runs Through It), “[even] the garbage man. And the notes always conflict.”
Since the desires of the studio, producers, director and actors are usually mutually exclusive, all of them will blame the writer, who will be fired and replaced by a new writer... taking the whole process back to stage 1. That’s Development Hell.