The AK was designed to be, more or less, an individual, handheld machine gun, spitting out volumes of fire. Robustness and reliability are paramount to pinpoint accuracy, although the triggers can be pretty good. The 7.62x39 round has good barrier penetration and is a stopper, but is has a pretty good kick. The stock sights and sight radius are not so good and the angle of the standard wood stock promotes muzzle flip. Those things can be corrected with modifications and fortunately modern AKs with rails easily lend themselves to the addition of red dot scopes and other optics.
Also, like anything else, you get what you pay for. Milled Bulgarian rifles (and even the pistols) are capable of pretty good accuracy out to 200 meters or more.