The higher the price, the stronger the demand. Under the condition of constant cost, enterprises certainly have the incentive to produce more to meet the needs of consumers and earn more money. If the price of a commodity is too high and deviates from the balance between supply and demand, it is not the real price.

The change of value is the internal and leading factor of price change and the basis of price formation. However, because the price of a commodity is determined not only by the value of the commodity itself, but also by the value of the currency itself, the change of the commodity price does not necessarily reflect the change of the commodity value. For example, when the commodity value remains unchanged, the change of monetary value will cause the change of commodity price; Similarly, the change of commodity value does not necessarily cause the change of commodity price. For example, when commodity value and monetary value change in the same direction and proportion, the change of commodity value will not cause the change of commodity price. Therefore, although the price of a commodity represents its value, there are still cases where the price of the commodity is inconsistent with the value of the commodity. Under the condition of simple commodity economy, commodity prices fluctuate directly around its value with the change of market supply and demand; Under the condition of capitalist commodity economy, due to the competition between departments and the equalization of profits, commodity value is transformed into production price, and commodity price fluctuates around production price with the change of market supply and demand.