How many words per day and per week are enough to make novelists feel that they're being productive?

How many words per day and per week can we write and still be sure that any of our sentences, let alone all of them, are effective, moving, or beautiful?

Each novelist differs in temperament, talent, and stamina. And our goals differ as well—from writing for ourselves to aspiring to sell as many novels as James Patterson.

I write for myself in the sense that I feel best about my existence, my drive, and my abilities when I'm writing. In only that sense, however, do I write for myself.

I rewrite and edit for my readers.