I have found that many people in America, and other countries outside of Asia as well, just assume that because a person is Asian, they know the Martial Art. If I have two beginner students who are forty year old males, one an American and the other a Korean, and anyone saw them going into a Taekwondo Dojang, they would most likely assume that the Korean was a high ranking master.
Often times, foreigners from many different countries migrate to America, and become citizens without speaking very much English (if any). They cling to the traditions of their native country. However, their U.S. born children grow up as Americans, knowing very little of their parents. native tongue, and even less about the culture of their parent's homeland (this is not always the case, but often happens this way).
Korean children born in America are just like any other kids. People often assume that because they are Korean, they should automatically know the Korean language, or how to do Taekwondo, etc. The truth is, they are learning just like anyone else. They start as beginners, they get nervous at testings, and they forget terminology or how to do a form.
This might cause their parents embarrassment more than anything. They figure that other Americans expect a Korean to do well at speaking the language, and performing Taekwondo, so they try to live up to those expectations. If the parent becomes angry with the child for getting it wrong, I think it is a combination of two things. They are parents who expect their children to do well, and they are embarrassed because they are Korean, and their own offspring does not know the language.
I have noticed that the culture of Asians, when it comes to education and their children performing well, usually applies a lot of pressure. You find a lot of child musicians, from Asian countries, playing the piano or violin like they were born to play. These children often look like they are denied a childhood of fun and play to study music, or math, or rocket science.
On the other hand, I have noticed that many people outside of the Asian nationality often view the Martial Art as something more special, mystical, and worthy of serious dedication. Many Asians take it for granted because it is something they have readily available to them in their country. It is kind of like baseball in America. Most kids have tossed around a ball, or played a game as a kid, but how many kids go into professional baseball? I believe the Martial Art is much more than a sport, a hobby, or just a system of self defense, but it often takes an Non-Asian to see the special qualities the Martial Art has to offer. I just wish more Americans would take it more seriously, and studied it more thoroughly.
As for the Korean student - - kids will be kids!
CM D.J. Eisenhart