Stop Revising Your First Chapter
Many writers get stuck in perfection-mode, forever revising their beginning chapters but never finishing. They post the chapter on a critique sight, or pass it to fellow writers at their writing club, then analyze the comments, revise, and repost. The cycle goes on and on.
Don't do it. Oh, you might rewrite your first chapter the first time someone reads it. All writing is good practice. But not again. If someone suggests a change, just make a note, but keep going on the next chapters, all the way to the end.
I'd put down money (and win more than lose) that most writers end up scrapping their first couple of chapters by the time they reach the end. They decide to start the story at a different location or time, or they have changed their protagonist from married to unmarried because that fit the story better, or make some other alteration which contradicts what is written in chapter 1.
One of the most common reasons why editors find themselves advising new clients to drop their first two chapters is because inexperienced writers tend to start novels at the wrong place. They think the reader needs to know a ton of backstory before the action starts or they start with preparation for action, not action. I see this often with young writers, a surprising number of whom start their story with their main character in bed. Editors see this so often that many don't bother reading past that first paragraph. "The alarm rang. Beth yawned, and punched the snooze button."
Well, the editor just yawned, too, and dropped the submission into the "no thanks" pile. You wouldn't believe how much this happens. If something exciting was about to happen to Beth at school lunch break, the author should have started the story with the lunch bell ringing, not the morning alarm clock.
A few years back I took a workshop at the Maui Writer's Conference from John Lescroart, crime novelist. He told us his writing procedure. He starts in genius mode, assuming that everything he writes is perfect. He races through to the end. Then he takes a week off. (Not just for rest, he says, but it's important to get the story out of his head.) Then he starts going through it in idiot mode, where he assumes that everything he has written is garbage, and tries to discard the trash and rescue the good parts. It's in garbage mode where he finds all those things that contradict each other, the subplots that didn't work, the way his character's behaviour was illogically different in later chapters from earlier. On third pass he looks at every sentence and tries to make it the best sentence it can be.
He writes a novel a year, and most of them become bestsellers.
One of the other writers at the conference--I can't remember who it was--said she writes a few chapters. The next day goes back over them once and moves on. She never goes back more than one day. After she reaches the end, she starts back at the beginning. I remember her saying that she usually scraps the first couple of chapters, too.
Very few people who start novels make it to the end. Get there first, before revising. If you think of something midway through, like giving your protagonist a brother, or change his backstory by having him grow up somewhere else, just make a note to fix it in earlier chapters and keep going.