Russia has made mistakes in its “Special Operation” against Ukraine, but it apparently learns from them and adroitly changes course. From Marko Marjanović and Mike Whitney at unz.com:
Question 1 [Whitney]– The war in Ukraine appears to be shifting eastward to an area in the Donbass around the city of Krematorsk. This is where upwards of 60,000 Ukrainian combat troops are “dug-in” and prepared to take on the advancing Russian army. In one of your posts, you suggested that the “real war” is about to begin. Most of the military analysts I have read, seem to agree with you on that point. Some analysts, however, think that it could take up to three weeks for Russia to assemble the troops and material needed to launch a full-blown offensive. Others say the artillery phase of the battle has begun already. In your opinion, will the upcoming battle determine the outcome of the war? Also, what will it take for Russia to prevail in this extremely challenging fight against an entrenched and capable army?
[Marjanović] I have no idea how long it takes to get the forces that were in the Kiev operation ready for a coherent, ambitious and well-supported effort in the southeast. We would need a staff officer to tell us that. Somebody who knows trains.
Generally speaking, better-prepared offensives work better. The element of surprise now being out the window, you want to err on the side of too late rather than too soon. Taking a few extra days for buildup that you didn’t really need, is far better than starting a few days too soon.
Throwing forces into attack before you are able to properly back them — with opposite arm forces for support, supplies to sustain their success, and follow-on forces to exploit it — is the surest way to have wasted effort, and casualties with little to show for them.