The lines remain static mostly by Ukraine defending. They fight off attacks, return, and wait rather than press. For a while they’ve had geographical advantage and have stuck to it tactically for sake of fewer units.

The loss of Adviika got messy, but they had already mostly pulled back before Russia realised, causing lots of unexpected damage from new positions as Russia came in.

Truth is they’re fighting extremely well in comparison. They’re the much better side, but a smaller force. This is why it’s imperative we keep supporting so they can keep holding as well as they are. Tactics eventually only go so far in wars of attrition, especially against Russia’s nonchalant behaviour of throwing in meat to eventually wear the grinder out.