The Battle for Kyiv March 12, 2022

[Wounded Bear]

2. The farther into Ukraine they drive, the longer their supply lines grow...

and they become more exposed to small unit attacks that can snarl roads and demolish vehicles in their rear. Knock off the lead and last vehicle in a convoy and the rest get stuck in the kill zone.

They're not controlling the countryside well, and some gutsy small units can infiltrate and attack their rear areas. The Russians can provide security for their convoys, but that takes troops away from the front lines. It's the bane of all invading armies.