Overall, both theories are against the ailments produced by a capitalistic society. The main argument against capitalism is that the working class labors so the upper class can make most of the gains without devoting much of the labor. This creates an imbalance in society and forms an unfair system that only benefits the few. Many argue that this simply creates new "nobility". Capitalism favors the ownership of private property and those who own property, such as factories, have the option of passing on their wealth and business to their offspring. Meanwhile, the workers within these factories are always in competition with each other and end up working for subsistence wages.
Socialism and communism were constructed to counteract this unfair political model of capitalism. As theories, they were produced with the working class in mind. The objective was to provide workers with more power. At the time of the rise of capitalism (during the Industrial Revolution in Europe), workers had no rights as an organization. Since the notion of a working class was completely new, there was no organization, even amongst the workers themselves. No unionized groups (known today as "unions") were recognized and therefore there were no negotiations conducted with employers. In addition, any attempt by the workers to organize or rebel was quickly crushed. It was becoming apparent that employers held absolute power over employees, their wages and their working conditions. Socialism and communism transferred power back to the workers by allowing them to equally and fairly distribute the wealth. The workers would benefit since they could now fairly set their working conditions. This in turn would cause the entire country to benefit because workers would have more of an incentive to be productive.