How a single seller in the market can maintain inefficient allocation of resources?

A single seller, or monopolist, can maintain inefficient allocation of resources by setting prices above the marginal cost of production, which leads to reduced output and higher prices for consumers. This results in a deadweight loss, where potential gains from trade are not realized, as some consumers who would benefit from purchasing the product at a lower price are priced out of the market. Additionally, the monopolist may have little incentive to innovate or improve efficiency, further perpetuating resource misallocation. As a result, the overall welfare of society is diminished compared to a competitive market scenario.