Gains cannot exist apart from the concept of use value. Therefore, profit has both the aspect of value produced during the production process and the aspect of gain formed in the circulation process. But the aspect of value itself means nothing but the use value of a commodity. When producers supply consumers with value, they are given profit as their reward. That is actual profit.
Profit is the social reward for the activity of creating value, through investment.
Here, value means use value, that is, the commodity itself, whereas the activity of creating value means those creative activities of production, transportation and storage, etc. After producers or merchants produce, transport and store commodities, they supply and display them for the convenience of consumers' purchase. The reward which consumers return to producers or merchants is profit. According to Marx, capitalism will inevitably lead to ruin in accordance with certain laws of economic movement. In order to gain as much profit as possible, capitalists compete for introducing new machinery.