Short answer:
The idea of the National Novel Writing Month is to reach 50,000 words, starting 1 November, ending 30 November. This means pushing. If you have the scene in your head, write it, whether it's the next thing in the time line or not.
You aren't supposed to polish or edit, just output. Unfortunately, I can't do that. At least I can keep my output up to minimums (1667 words a day, on the average). As long as I make that, I let myself edit.
But as a result, if a scene isn't there, I skip to one that is. December is "Well, let's whip this manuscript into something edited" month. There's no obligation to ever do so. But if you've got your 50,000 words, it's tempting to work on it more.
Unless it's pure garbage. If I thought it were pure garbage, I wouldn't bother showing people.
Maybe the pieces you want to see will never be written. Maybe if you want to see it, I'll write it for you -- but after the easy stuff is written.