That's why I've never liked the Koreans. I've worked with some of them in a Hyundai affiliated factory in Gwangju before. They are rough mannered, talks loudly, pull your sleeve when calling out to you and are very unreasonable in arguments. When I asked them why, during the early days of Hyundai Motors, does it still collaborated with Mitsubishi Motors when they hated Japan so much? He replied unashamedly that the collaboration is to try and steal Japanese technologies. Also, they will try to cut corners at every possibility.
They are akin to the present day Chinese. All those from the DongBei (North Eastern) China behaves like barbarians. Koreans are the descendants from this region, hence the similarity in behavior.