He is everything that is wrong with the workplace.

This might be a hot take, but nobody does a better job because they are constantly being screamed at by a superior. If you’re continually being criticized, no matter how well or poorly you perform a task, you’ll likely feel like trying hard is a fruitless endeavor, so you stop trying. 

There’s a difference between talking loudly, as people from different cultures often do, and yelling in a way that berates or belittles somebody. Getting yelled at by a family member or coach is bad enough, but having to put up with your boss screaming at you is a whole different level of demoralizing. In that scenario, your literal ability to survive relies on your willingness to tolerate disrespect. You can’t just walk out of your job if you don’t have anything lined up, especially if you’re living paycheck to paycheck. Of course, you don’t have to put up with it. You can always leave a bad job and find a new one, but that requires a level of self-respect and willingness to get the respect you deserve.