1. Character development
I spend time just thinking about my characters, what they say in different scenes, what they sound like when they talk, the quirks they have, etc. It gives me a chance to get to know them before I attempt writing their stories.
2. Plot development
I think a lot about plot during this time as well, and often the fun twists come to life at this point. I like to be thorough with this step and know exactly where my story is going--from beginning to end--before I invest any time in writing a whole draft. It helps to avoid plot holes so that I don't ever get to point "C" and wonder how I'm going to get to point "H."
3. Prevents writer's block
Because who wants that disease? If I have things mapped out in my head, I don't typically get writer's block. I mull over my unwritten book in my imagination until it is as visual as any memory. It makes writing easier, smoother, less frustrating.
4. Gives you that glossy look in your eye
Don't deny it. We've all been there before. When people ask you what you're daydreaming about, feel free to set them straight. "It's not daydreaming," you might say. "It's brainstorming. There's a big difference."
5. Helps make important decisions
For example, which point of view would be best for your story. POV rewrites are not fun. I need to be able to "hear" the voice of the story before I try to write it. It needs to be a strong one, the strongest possible, and that doesn't happen with hasty writing.
I mentioned in my last writing post the importance of writing things down. Because things become so visual for me at this point, I don't have to write them all down, but some things I do. Often during the brainstorming phase things come in the middle of the night. I'm more likely to forget these things so I keep a notebook close to my bed just in case.
What is your brainstorming process like?