Ever try to plug something in behind the couch or in an unlit room (say, for instance, a lamp needed to light that room)? The directionality of plugs may be their biggest everyday drawback.
Thus the Donut, with its continuous circular slot so that (at least in countries employing such shapes) you do not have to see what you are doing to get your devices powered up.
No more worrying about up, down, or upside-down, nor bent prongs and jammed hands or (un)fun with flashlight acrobatics.
Suhyun Yoo, Eunah Kim & Jinwoo Chae may still have to contend with convention – not to mention fire code and electrical compatibility – but the concept seems sound.