The article looks at how different firms from around the world perform in the same market. They found that the number of products a firm offers, the quality and efficiency of those products, and the variation in these factors all play a role in how well a firm does. Quality is the main factor that sets firms apart from each other. The study also shows that countries with more diverse markets tend to have a wider range of firm performance, especially in terms of quality. Superstar firms are more likely to be found in these countries, but they are not the only reason for the variation in firm success.