Hollywood is a screenwriter's town. Why? Because Hollywood is a movie town, and although movies don't always start with a script – it's quite common for talent to get attached to a project based solely on an outline or concept – eventually, the script is written. And the finished screenplay really does become the film's foundation. Hitchcock wasn't alone when he said: "The three most important parts of a film are the script, the script, the script."
But despite this good news, there is still a problem. Even though Hollywood is a town that lives and breathes screenplays – one of the most daunting tasks for the screenwriter is to submit his or her script to the people in power: industry executives, producers, and agents. The best script in the world will go unnoticed unless it is read by the movers and shakers in the industry, whose stamp of approval is necessary to get the movie made. When that happens, you're cooking... American barbeque style. If not, you're stuck with a ton of raw meat.
But there's a second obstacle as well. Assuming you're lucky enough or know the right people to get your screenplay read, the probability of rejection is high. Anyone who's the arts knows this already – rejections simply come with the territory. Thick skin is necessary to survive. The problem, however, does not rest with rejection. Instead, it's the frustrating experience that the "no" almost always never comes with any useful advice or honest explanation as to why it the script failed.
Now I don't mean to imply that agents, producers, and creative executives can't give amazing and very focused feedback. But when it doesn't happen, you should never be satisfied with the "no" answer. You're the writer, but your job doesn't end upon completion of a draft. Conversely, completing one draft only initiates the beginning of the second or third or tenth draft. But if you don't know what the problem areas are, how can you repair them?
This is why I urge every writer not to be afraid to ask for clear and honest feedback. The squeaky wheel does get the oil. So when you're rejected, do yourself an enormous service and ask the person who said "no" for an explanation as to what was behind the rejection. Remember, you usually won't receive useful rewriting advice unless you ask for it.