But nobody goes from writing 0 words a daily to Nanowrimo and comes out the other end as a "better writer" without having some sense of discipline and writing regularly. Doing anything besides eating and sleeping every day is hard. If you can get to the point where writing 250, or 750, or 2,000 words a day is a given, then you can focus on actually getting better without having to worry about the effort required simply to put words on the page.

I agree that writing daily doesn't necessarily makes you a better writer, but usually it helps a lot. Also, writing your thoughts as often as possible gives you more sense of clarity.