Final answer:
Larger or established businesses may leave gaps in the market, which smaller ventures can take advantage of. Possible reasons for these gaps include poor management, unproductive workers, tough competition, shifts in demand and supply, and changes in prices.
Step-by-step explanation:
In the model of perfectly competitive firms, businesses may leave gaps in the market for various reasons. These gaps can then be identified and exploited by smaller ventures. Some possible reasons for larger or established businesses to leave gaps in the market include poor management, unproductive workers, tough competition, shifts in demand and supply, or changes in prices for inputs and outputs.