Sometimes, waiting is a part of writing. (It's definitely a part of publishing, but that's a whole other blog post.)
Waiting until we know what happens next, or how, or why, or when. Waiting until we're ready to write that book, or that scene. Waiting for enough perspective, or courage, or willingness, or empathy, or independence, or confidence. Waiting until we have the skill, or have done enough research, to handle a certain topic or story. Waiting until the draft cools off enough for us to read it (somewhat) objectively. Waiting to ask for feedback until we're ready to hear it.
Waiting is not the same thing as procrastinating. From the outside, they can be hard to tell apart, and we can tell ourselves that one is really the other. But the gut knows. Frustrating as it can be, there are times when waiting is the best thing I can do for a work in progress.