The rhetoric from Russia went
from de-nazification, which means the southeast regions,
to preventing nuclear arms in Ukraine, which mean the capital and the government,
back to only the de-nazification, after the failure of the blitz,
and to fulfilling the Ukrainian policy of ridding itself of the communist influence, which from Russian perspective is going back to the borders of the 1920's.
So, Russians won't stop until Ukraine becomes a landlocked country. This will go on for a decade. The second war in Chechnya, for reference, lasted close to a decade.