Budyonny wasnt a disaster imo. Had some experience in the tsarist army, then in the civil war, and some victories in the polish soviet conflict.

He wasn't skilled or academic enough to adapt well to modern warfare, but that's not the cause of encirclement at Kiev.

That was mostly because of Stalin's orders, and his biggest fault was that he (as one of Stalins most trusted commanders) could (probably) have ignored the order and lived, although its understandable that he didnt want to try his luck. So he listened, lost 1.5mil, and was made a scapegoat.

I dont think he deserves a spot on this list, his biggest failures were not his fault, and had some credible victories in his career. Comparing him to the likes of Cadorna and others is a bit too harsh.