At Elite levels, karate is a very fast sport. Kicks and punches can be delivered as fast as four per second, too fast for the naked eye to notice. Even trained judges are human, and such thigs as stress and fatigue can affect their performance.
The latest remedy that was introduced to combat this deficiency is video review. However, video review introduces its own problems.
First, frequent interruption of the bouts by the coaches detracts greatly from the visual appeal of the sport. Basically, coaches are free to stop the bout and ask for video review after each and every score by the opposing athlete. While judging panel is rehashing the video, both athletes and spectators linger.
Second, video review is still done by a subjective panel of humans. In extreme cases, like the one described in the sidebar, the review can be a source of a spectacular error that does untold damage to the athletes and the sport karate.