Robert Heinlein wrote a famous list of rules for writers:
"1. You must write.
2. You must finish what you write.
3. You must refrain from rewriting, except to editorial order.
4. You must put the work on the market.
5. You must keep the work on the market until it is sold."
Strikingly, these are all paraliterary rules, rules about staying in the game and not letting the bastards grind you down. No stylistic advice is included -- indeed there's a strong suggestion you shouldn't worry about style. This is particularly true of Rule 3, which hardly any writers would agree with.
Isaac Asimov wrote somewhere that he always wrote two drafts of everything, and that Heinlein advised him to write just one draft instead, but that when Asimov tried this method he found it unsatisfactory... not that two drafts are very many either.
I find it hard to believe The Door Into Summer is really a first draft... but perhaps there are reasons Heinlein needed fewer drafts than other writers. He turned to writing when his views of how the world worked were already well-formed -- and in science fiction, a movement then near the height of its vigor and commercial viability, he found a genre ideally suited to expressing his pragmatic and Libertarian attitudes. Perhaps this helped him feel his thoughts were valid in whatever form they first came to him. Alternatively, claiming he never had to rewrite anything may just have been a ruse to disgruntle other writers.
Robert J. Sawyer offers a restatement of Heinlein's rules, including a less-objectionable version of rule 3 -- the second draft of rule 3 that Heinlein never wrote!
"3. Don't tinker endlessly with your story."
Perhaps that's what Heinlein really meant. Sawyer also adds a sixth rule, entirely in the spirit of the first five.
"6. Start working on something else."