You've heard some version of the cliche that most writers who are in the struggling phase of their career are frustrated. And this causes their writing to suffer. There's some truth to this, but it's not the writing that suffers, but their personality. Always being in a half baked critical frame of mind where their always trying to demystify something. It could be the writing process itself or what motivated someone to take an approach and where it faltered. This keeps the writer in a pendulum of mood swings between dealing with the success and failure of their ideas throughout the day. So where does this come from? It comes from wanting to be a writer. Definitely, not from wanting to be a bodybuilder or scientist. As a writer you're job is to come up with your own ideas in an effort to entertain for money. With the others you can give yourself a reward for doing something that shows progression or you could regret something for something out of your control. This is why most normies seem so level headed and mature. So why can't writers see the good in what they do? It's because writers don't like everything that has to do with writing. Even the most hardcore metal head can listen to a rap song and in all honesty find it tolerable. Writers usually can't do this. If you only like big commercial blockbusters, you will not like anything what Tennessee Williams or Arthur Miller have to say. But you shouldn't worry about liking everything on purpose or a having a negative opinion because if you're a writer, this is who you are. You're not a normy without pressure to think in scenes and sequences of people doing things day in and day out. You're not a painter who enjoys every color more or less. You're not a coach in the NFL who has to decide whether to run right or left. Unlike these things, personal criticism is going to come from other writers and you're going to have to dish it out yourself for whatever reason, but the only reason you and they care so much is because it's just what a writer's lifestyle includes!