Incomplete question. Assumed you are referring to this article;
Six years after turning the leadership of Costco Wholesale over to the then- president, Craig Jelinek, Jim Sinegal, Costco’s co-founder and chief executive officer (CEO) from 1983 until year-end 2011, had ample reason to be pleased with the company’s ongoing revenue growth and competitive standing as one of the world’s biggest and best consumer goods merchandisers. Sinegal had been the driving force behind Costco’s 35-year evolution from a startup entrepreneurial venture into the largest retailer in the United States, the seventh-largest retailer in the world, and the undisputed leader of the discounted warehouse and wholesale club segment of the North America retailing industry. Since January 2012, when Craig Jelinek took reins as Costco Wholesale’s president and CEO, the company had prospered growing from annual revenue of $89 billion and 598 membership warehouse at year-end fiscal 2011 to annual revenues of $126.2 billion and 741 membership warehouse at year-end fiscal 2017. Costco’s growth continued in the first nine months of fiscal 2018. 9-month revenue was $95.0 billion, up 12.0 percent over 9 months of fiscal 2017, and the company had opened four additional warehouses. As of June 2018, Costco ranked as the second-largest retailer in both the United States and the world.
Step-by-step explanation:
Note, the threat arising from new competitors into a particular market refers to the likelihood that this company or business would overtake existing ones in their market share.
However, recall that we are told that Costco has been in the business for up to 35 years, and has become "the undisputed leader of the discounted warehouse and wholesale club segment of the North America retailing industry," this fact alone makes us and the new competitors weary of how difficult to acquire part of the market. This thus puts Costco at a competitive advantage.