Employees are (or should be) given more rights/protections than the employers because they have less individual bargaining power. The rights are there to counterbalance. For example it shouldn't be as easy to get fired as it is to quit.

The country's culture matters a lot. The same system that works perfectly in a healthy society will end up an abusive nightmare in an unhealthy one. Mobility for salary raises can also become mobility just to keep a job.