I think sometimes workers need to protest about unfair when they can't accept what happened in workplace reasonably.
Their protesting means showing something what they think to employer and other people.
After protesting, if the employer fix something wrong, it could be effective.
But sometimes the employers and employees don't understand each other. If there is no changes, they still have problems.
So I think all workers need a good working environment and they want to be treated fairly and to be evaluated by their abilities.
If a good working environment is ready, workers work harder and they can get a good result. And also it will improve productivity.