In an oligopoly, firms have market power and can influence prices. What is the main characteristic that allows these firms to earn economic profit in the long run?

In an oligopoly, a few large firms dominate the market, which gives them significant control over prices. The main characteristic that allows these firms to earn economic profit in the long run is the existence of barriers to entry. These barriers can include high startup costs, strong brand loyalty, or control over essential resources, making it difficult for new competitors to enter the market. For example, if a few companies produce smartphones and have established a strong brand presence, new companies may struggle to attract customers and compete effectively. As a result, the existing firms can maintain higher prices and earn profits over time without worrying about new competitors taking away their market share.