Answer:
1. no.
2. no.
3. as many times as you need.
Step-by-step explanation:
1. No writer in history has ever followed a specific agenda to create the "perfect piece". It doesn't exist. Writers tend to just go with the flow and let creativity seep through the pen ink.
2. Every writer has revised their work (of course if they truly cared about it), and it's alright to make mistakes. What's important is that you correct them and learn from them. You do not need to really hit it out of the park on the first go if you aren't comfortable with it.
3. Many, many times. It may be appeasing to someone else but it may matter to you a lot. Just don't sweat it, practice makes perfect. You're only human.