A Comfort zone is where most of you are now. A job that is not good for you, but better than unemployment anyway. A relationship that is not good but better than loneliness. A house that is not good and big. But at least you can sleep in it at night.
You are not satisfied in your safe area, but because you are used to it and it gives you a false security. You stick to it and do not travel to other areas of life.