What was the contradiction between the proletarians and their employers in the 19th century in Europe?

What was the contradiction between the proletarians and their employers in the 19th century in Europe? And what is its consequence?

The main contradiction between the worker and the capitalist: the worker wants his labor to be valued as expensively as possible, and the capitalist wants to buy labor as cheaply as possible in order to get the maximum profit. New mechanisms that appeared began to crowd out those workers who could not quickly rebuild to new conditions. The more complex the mechanism was, the more qualified the employee should be. These contradictions led to numerous protests by workers against the capitalists.