Seriously...I stick to a 2000 word per day quota. On the best of these days, it's 2k (or more) of directed, fairly polished narrative. On the worst it's blathering nonsense. Mostly it's part warm up, part salvagable prose, and part meandering.
If a writer is serious, this is the way to go.
It's
a way to go.
Iain Banks, to take an example of a published author who must have more than twenty novels out by now, some of them really excellent, has said quite a bit about his process in public, which seems to involve ten months or so of messing about and two months of writing in a panic, which has pretty reliably got him out a novel a year or so for the past twenty-odd years. I'm aware of several other published authors with good careers writing good books who work in spurts. On the other hand, there are people like Terry Pratchett, whom I have seen enough times in conventions disappear into quiet corners to write for five and ten minutes at a time that I can believe he's not writing to a quota so much as needing to fill every available quiet moment with writing; it must be very nice to be able to afford to do that.
There are some published authors who are very much behind writing every day; Stephen King and Harlan Ellison, IIRC, have been quite vehement about it in print. And if that works for you fine. So far as I am concerned, what matters is having some way of being sure that words are ending up in the page, and not making excuses for not writing when you can; my own pattern, of usually two to five thousand words every Friday night - sometimes moved to another night if for example it's my stepson's birthday on a Friday, and with occasional spurts of more if the inspiration takes me - seems to work fine in terms of getting a new chapter every week or two and a new completed novel every year or so. Being vehement about
having to write every day can be a bit discouraging to those of us who have combinations of jobs and family lives that just do not permit that.