When it comes to career advancement what is meant is to improve within your working life. If you, for example, start as a small worker at an assembly belt in a manufacturing company and then you will be promoted from your direct boss to a secretary then this is career advancement. And if you are then promoted from a secretary to an assistant with your own office this is even more a career advancement. This type of career advancement within one and the same company can go on until you, yourself, will be manager, for example.
Career advancement, however, can also be realized with more than one company. You can for example get a job as an assistant in one company and after two years, let us say, you come across a job ad with a better position suited to your education and now even experience. You apply and you get it. If that is the case, then this was also a successful career advancement because you are a step higher. Once you are a step higher in your career advancement you will most certainly not step down or back anymore. This is the purpose of career advancement. Once you are up you are up or can even climb further.
Career advancement, however, always involve your profession. This means that you will not be able to work as an engineer and then all of sudden have a career advancement in the way that you become the host of the most famous and successful TV show or become managing director of a bank. So, career advancement is done within your profession. The aim of any career advancement is of course, to earn more money.