"There are other similarities between Ukraine and Iran. Both are wars instigated by the leaders of great powers in the apparent belief of easy victory. Both have developed in ways those leaders did not anticipate into something like a stalemate—stalemates in which, for Russia and America alike, a lack of victory looks increasingly like defeat. Are technological changes making the role of the defender easier? Or syste…
And where does your inside info from the Kremlin and Putin's head is coming from?
Putin was raised in the KGB, I think he knows a bit how to get intel. And with secret war style he was very successful in 2014 seizing the Krim and some areas.
It was likely just overconfidence in the ability of the russian army in a conventional war and underestimating the will of the ukrainians to hold their ground in the beginning of the war.
If that battle in the beginning would have turned out different, Kiew would likely have fallen and then the war would have been largely over in a few days
https://en.wikipedia.org/wiki/Battle_of_Antonov_Airport
Not many believed, myself included, that Ukraine was strong enough to hold of the russian army - but they did. And now both sides use Drones heavily.