I haven't seen the movie yet, but I read how the film came about in an interview with the director. The director wanted to make a story about "forgotten father" and remembered his father, who worked with his ox all the time. He says the saddest thing in the world is not disappearing, but being forgotten. He had to awaken his father and the ox "sealed" in his childhood memories and wanted to bring the memories back to present. He was then searching for an old ox all over Korea and met the old man and the ox and started filming in 2005. This movie is a dedication to his father and all fathers who seem distant to their children. He wanted to depict such relationship (or lack thereof) in this film.