The BTS coffee and Pepsi Cola advertising cases in Vietnam demonstrate that simply relying on the popularity of Hallyu stars is not enough for successful overseas market entry. Just as the popularity of Park Hang-seo, the coach who led Vietnam to victory in the Suzuki Cup, did not influence the promotion of Korean consumer goods, the popularity of Hallyu stars does not directly affect product success. Vietnamese consumers may like Hallyu stars like BTS or Blackpink, but their image alone does not guarantee product sales. The key is to accurately understand the needs of local consumers and develop products and marketing strategies that meet those needs. BTS coffee did not match the coffee preferences of Vietnamese youth, and Pepsi Cola was no different. Ultimately, the Hallyu wave is just one factor in overseas market entry, not a universal key. Korean companies need to understand the needs of local consumers and develop products and marketing strategies that meet those needs.