Before I came to South Korea, I had done some research on what to expect from life here. There were many positive things, like the public transportation and the safety of cities. There were also some things to watch out for, like how working overtime is almost an expectation. However, there was one thing that many people agreed was a shock when they first came to Korea: not seeing their favorite celebrities everywhere on the streets of Seoul. Since South Korea is a small country, many people come here with the expectation that they will get a chance to interact with their favorite celebrities or that everyone in South Korea will look like an idol. Unfortunately, that is not the case. Imagine if you had a friend visit you from abroad, and they were disappointed that they didn't meet Justin Bieber at the grocery store. Or if they were surprised that your school principal didn't look like Margot Robbie from the Barbie Movie. From your perspective as a native, you understand that these are unrealistic expectations, but when people travel to new places, they come with many dreams and expectations of what that country will be like.
That does not mean that there is a zero percent chance of seeing your favorite celebrity in South Korea. Rather, it is far from zero percent.