From author John McPhee’s encouraging words to his daughter when she was frustrated at a senior high writing assignment:
“Blurt it out, heave out, babble something out – anything – as a first draft.
With that, you have achieved a sort of nucleus.
Then, as you work it over and alter it, you begin to shape sentences that score higher with the eye and ear. The chances are that about now you’ll be seeing something that you are sort of eager for others to see.
And all that takes time.”

“You finish that first awful blurting, and then you put the thing aside. You get in the car and drive home. On the way, your mind is still knitting at the words. You think of a better way to say something, a good phrase to correct a certain problem.
Without the drafted version – if it did not exist – you obviously would not be thinking of things that would improve it.
Your mind, in one way or another, is working on it twenty-four hours a day – but only if some sort of draft or earlier version already exists.
Until it exists, writing has not really begun.”

John McPhee, Draft No. 4 On the Writing Process