Syd Field "Screenplay: The Foundations of Screenwriting" 43rd Publication Anniversary.

"To the students, writers, and readers of the screenplay - everywhere."
When you complete your screenplay, you have accomplished a tremendous achievement.
You’ve taken an idea, expanded it into a dramatic or comedic storyline, then sat down and spent several weeks or months writing it. Inception through completion. It’s a satisfying and rewarding experience. It’s been your best friend and your worst enemy. It’s kept you up nights and let you sleep like a baby…
Commitment and sacrifice are two sides of the same coin. Wear that proudly.
Talent is God’s gifts. Either you have it or you don’t.
Don’t let selling or not selling your screenplay alter your internal state of mind, your feelings about yourself. Don’t let it interfere with the experience of writing. In the long run, you did what you set out to do. You fulfilled your hopes and dreams, fulfilled your goal.
Writing brings its own rewards.
Enjoy them.
Pass it on.