I would always think about leaving if I found, that my work is not appreciated enough and there is no chance to switch position within the company to another department any time soon. All this considered, it would always depend on your financial situation and your age: a) are you fully qualified to take the next career step or should you rather stick around to take more courses, exams, certificates etc.? Does your present company offer and encourage the professional enhancement of its staff and even take over some of the cost? If the answer is YES, you should stay or look for another job that offers just that.
b) Are you personally unhappy by job surroundings and the people with which you have to interact on a daily basis? Do you feel insulted and abused? Then get out as quickly as you can afford to. Most of us are not 100% happy with our jobs, but at least you should feel satisfaction about your day's work and live in harmony with your colleagues. Anything else will make you sick in the long run. And don't forget: health is your greatest asset on the job market - besides education.
b) Are you personally unhappy by job surroundings and the people with which you have to interact on a daily basis? Do you feel insulted and abused? Then get out as quickly as you can afford to. Most of us are not 100% happy with our jobs, but at least you should feel satisfaction about your day's work and live in harmony with your colleagues. Anything else will make you sick in the long run. And don't forget: health is your greatest asset on the job market - besides education.