Why the Rise of Tablets?

Interesting article in the Chosun Ilbo English edition today, entitled "PC Market Stung by Rise of Tablets."  Indeed, the rise of tablets, not only in the South Korean market, but globally, is not at all surprising.  The reason for this is simply that, all other things equal, human beings prefer a mobile device, untethered by wires, to the old fashioned, wired desktop computers.  This is expressed succinctly in the so-called "Law of Mobility" or "McGuire's Law."
Having said this much, South Korea presents a special case in point.   I believe that Koreans are, culturally speaking, much more mobile than, for example, Americans.  Here I mean mobile in the sense of the percent of their average day spent outside the home.  I have no empirical data to present on this, but would appreciate observations.   Those of you who have ventured into the central district of most American cities after working hours might think of comparing that to any of Korea's cities when work in the office is finished.  Or, as the accompanying illustration (click to see full size version) shows, consider the average commute via public transportation in Korea versus commuting in a private vehicle in North America.  Comments welcome.