I live in Korea and teach children ranging from ages 4-13. I'm not disparaging Korean society out of ignorance, I'm currently smack dab in the middle of it and am speaking from experience.
I have kids that go to anywhere between 5-8 'hagwons' or private education academies in addition to their regular public schooling. The pressure on the kids to excel (placed on them by family and a society OBSESSED with material posession and image) is outrageous, so outrageous, that Korea has the highest suicide rate in the world among developed nations. Students make up a fair portion of that.
There's much more that lies beneath the veneer of South Korean commercial--and i would presume athletic--success. And in my experience, much of it is very, very ugly.