Hating your job -- where you spend the majority of your time -- is a destructive mindset which can poison a relationship. It's one thing to be mildly dissatisfied with work life while at work, but a man who is absolutely miserable at his job will spend a good amount of his free time being absolutely miserable about it as well, and that's not good. It's important to like what you do, and if this man doesn't, why is he still doing it? Why doesn't he change his career, or advance in it, or do his best to change his attitude? You don't want to date someone who gets stuck in an unhappy situation and doesn't do anything about it. Is this what he's going to be like if there are relationship problems down the line?