You're right about the 'quality' of troops, my mistake. But I still believe they failed largely due to a piss poor strategy and the belief that the Ukrainians would just roll over. Long lines of troops and supplies that were sitting ducks and when they did establish a front line then their supply lines were cut leaving them isolated.They didn’t send in poorly trained troops tbf. The 1st Guards Tank Army (Usually used for the defense of Moscow) were highly trained and well equipped. They suffered two heavy defeats, one in particular was Kharkiv where they were decimated. The Russians do have a lot of conscripts, but they still have some highly trained divisions in play.
I doubt they will make mistakes on the same scale again