It never fails. Every year, there will be some people who get discouraged because they're writing "crap". Or thinking that they might get encouragement from their friends and family, they show their work and get let down because they're being told that it's "no good." I can't stress enough that Nanowrimo is all about getting the words down--not so much the quality, true--but it is a draft.
And anyone who thinks a first draft is perfect is perfectly nuts.
There are perfectionists out there who want their first go around to be flawless. This is next to impossible. Writing is a lot like other things--you need practice to get better. An example: let's compare writing to doing a routine on the parallel bars. You'd be mad to think that the first time you do it will be good. For a non-gymnast like me, I'd probably hurt myself many, many times before I even reach passable.
So the mindset of this high velocity writing challenge is not really getting any output that is "good" or "bad." When you think of "disregarding quality", you should not make it synonymous with writing dreck. This is practice. Concern yourself with quality and editing after the month is over.