No it won't run and run since Putin isn't going to be staying in occupation of Ukraine. He isn't even going to attempt to occupy all of Ukraine. All he wants is the eastern two oblasts of Donbass (which are 100% Russian anyway) and a land link from there along the western flank of the Azov Sea to separate the Crimea from Ukraine.
On the map below he's effectively possessed Russian populated Donbass for a decade anyway and Russian populated Crimea since 2014, so all he needs to gain is the red hatched area to protect his Crimean based southern fleet. That's a minute part of Ukraine, but once he has it he can withdraw and leave the Ukrainians alone.
It will be a repeat of his withdrawal from Georgia after he'd completed what he wanted there. Then he'll agree with the outside world's requests to withdraw, thus showing himself to be a reasonable person after all.
Never ever underestimate Putin:
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