North Korean border guards have to face each other so they don't defect to South Korea!
The demarcation line between North and South Korea is marked by blocks of concrete and the two sides face each other. All South Korean guards in this area, by the demilitarized zone, are armed with pistols, and stand in a modified Tae Kwon Do stance with solid facial expressions, clenched fists, and sunglasses meant to intimidate the North Koreans. They must be at least 177 centimeters tall and have a black belt in Tae Kwon Do or Judo to serve at the border as a guard.
All North Korean border guards are armed with pistols, and are well-fed officers who stand in rigid military posture. In each space, two North Korean soldiers stand facing each other rather than the South, so that neither one can defect to the South, and another guard stands behind them facing the North to prevent anyone else from defecting. In front of him is a two-man guard post. The North Koreans are pretty serious about not being tainted by any outside sources.