Consider the following two scenarios:
Scenario 1: You have a work that enriches you and fulfills you internally. Your senior is not your boss but your mentor. He believes in you and your ability to do any task assigned. Even when you make mistakes or sometimes dodge deadlines, he doesn't make an issue out of it but tries to understand what has been bothering you. He has his complete faith in you and every time tells you 'you can' even when you're not doing your work as per his expectations.
Scenario 2: You have a work that drains you from the inside. Your senior is a dictator. He constantly doubts your ability to do the work assigned to you. When you make an error, he gives this mocking smile and says "I knew you couldn't do it all right". He expects you to be a machine rather than a human. Even when you do the best of your work, all that anyone notices are the mistakes you've made and not the good work you have done.
Now it is quite evident what scenario anyone wants to be in. Everyone likes scenario one and no one likes scenario two. If you're in scenario 1, you're happy, motivated and loyal. On the other hand, scenario 2 means unhappiness, frustration and ultimately doubting your own capabilities. There are always professions we choose and we have this constant pressure and need of making a career for ourselves. But I believe before career comes happiness. Being happy means choosing scenario 1. The work may not add much to your career but it will surely add a great deal to your happiness and state of self-esteem. But if you're in scenario 2 then even if the job pays well and is a stepping stone for a brighter life ahead, as long as you're stuck there you're losing your happiness and draining yourself from your self-esteem.
However, there's no way of figuring out before you start any work whether you're joining scenario 1 or scenario 2. If by some bad misfortune, you're stuck in scenario 2 then perhaps that's a test in your life. One must learn to be patient and tolerate. There is much to learn from that kind of experience too. If you can handle that, you can handle anything in the world. But then there comes a time when integrity and a sense of peace and self-respect takes precedence over career. One must know when that time has come. Until then lets just survive the test and carry on.