Appraisal
Your company has told you that your performance is not good enough, despite all the effort you have put in. This is because you refused to do work that was not in your job description, and your boss was unhappy with this. Your boss seems to think that he can ask you to do anything he wants simply because he is paying you, and he did not consider your concerns. When it was time for your annual performance review, you were disappointed to find that your expectations were not met. You wonder why your boss continued to pay you your salary if your performance was so bad, and why he never asked you about your performance, or put you on a Performance Improvement Plan. Unfortunately, office politics won out, and you lost your confidence.
It is important to consider the culture and boss of a company, as they represent the company. You must decide if you are willing to stay in a company that treats you like this, or if you want to take a stand.