The most successful people are the ones that plan for the certain events if their life. One such event is switching jobs or careers. Plenty of people are dissatisfied with their current career. This is usually because they started working there while planning on going somewhere else eventually, and ended up staying there for many years.
This is actually a common problem. If you want to change your career, though, you should prepare for such a life altering decision. While it can be tempting to just up and quit one day, that is impractical and dangerous. You may end up jobless for a lot longer than you would ever want if you do it that way.