A quote from Robert A. Heinlein from a book titled Of Worlds Beyond: The Science of Science Fiction Writing published in 1947.
“1. You must write.
2. You must finish what you start.
3. You must refrain from rewriting except to editorial order.
4. You must put it on the market.
5. You must keep it on the market until sold.
The above five rules really have more to do with how to write fiction than anything said above them. But they are amazingly hard to follow — which is why there are so few professional writers and so many aspirants, and which is why I am not afraid to give away the racket!”
I think these are as true today as they were in 1947. Even with the dramatic change of the market. I’ve already seen a lot of blogs that argue these rule. I think they boil down to being a very disciplined writer.
The most controversial seems to be #3. I take number 3 to mean don’t rewrite after you send the manuscript off. I could be wrong, but I bet he did a little rewriting before he sent a manuscript off.