I see no difference in Russian strategy in Kursk or on gaining territory in Ukraine. Why should Russia take unnecessary risks in Kursk? Pride, embarrassment? They've shown patience and in time they will drive the Ukrainians out of kursk, and in five years from now nobody will give a shit that it took a few months longer than it should have. The Kursk offensive was stupid and Ukrainian loss have been huge. And what have they achieved?
Kursk is a classic poison-pill trap that Ukraine fell for. The terrain there is absolutely open. Forget hills or bluffs, kursk region looks like a giant billiard table, with hardly a tree in sight and just humongously flat,open ground. So unless Ukraine gets hari-puttar's invisibility cloak, moving foward in Kursk = turkey shoot for the Russians.
From Russian POV, if you wanna sit 2 inches into my land that you cannot invade without taking 100:1 losses, thanks to terrain, all the while diverting forces from the main frontline, fine by me. I will just contain with skeleton crew, win the manpower equation and pin you down here while kick your ass where it matters more.
Which is what they are doing.
There is a reason why the battle of Kursk is the largest ever tank battle in human history and will remain so - its a giant flat pancake terrain with nothing in sight for like a 30-40km radius, if not more. THAT is the kind of terrain where 15,000-20,000 tanks can show up and shoot at each other without getting bogged down or restricted in just over a month.
To understand how perfectly flat and without trees kursk is, imagine what kind of terrain you'd need if you wanted ALL the tanks of Indian army, Chinese army, Uncle Sam *AND* Russia show up to one spot and duke it out for a month. THAT is the scale of battle of kursk and that is why invasion route via Kursk is certain death for the invader without obscene amount of armor coming through, because its a flat open turkey shoot terrain.
If Ukraine wants to sit by one of the biggest, vast open football field of the world, big enough to accomodate 20,000 tanks and threaten to run across it and get themselves killed by 15 child soldiers with a bandook - russians arent gonna chase them away just yet for being this level retards.