The prospect of greater market share and setting themselves apart from the competition is an incentive for firms to innovate and make better products. But no firm possesses a dominant market share in perfect competition. Profit margins are also fixed by demand and supply.
A perfectly competitive firm is a price taker, which means that it must accept the equilibrium price at which it sells goods. If a perfectly competitive firm attempts to charge even a tiny amount more than the market price, it will be unable to make any sales.
Perfect competition occurs when there are many sellers, there is easy entry and exiting of firms, products are identical from one seller to another, and sellers are price takers.
The market structure is the conditions in an industry, such as number of sellers, how easy or difficult it is for a new firm to enter, and the type of products that are sold.
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