10000 words per day is an INSANELY high number. Though some writers do manage that kind of productivity, it is not at all common.
My daughter and friend currently put out approx 1600 words per day (of excellent, barely-needing-editing output, cuz they've been at it since they were pre-teens, have paid their dues, and now truly understand the process). That adds up nicely. Me? A measly 500. (And not anywhere near as polished as theirs, cuz I haven't yet paid my dues/put in my time) but that actually adds up nicely, as well. :)