Baloney. Most "experts" expected the invasion forces to take Kiev and decapitate the Ukrainian government in days. It certainly looks like putin expected this, and he had the example of Crimea in '14 as precedent. He simply rolled the tanks in and that was that.
The fighting in Eastern Ukraine was the product of Russian aggression, no "little green men", tanks, artillery, airpower, no war and no danger to the Ukrainians living there. Russian manufactured conflict to facilitate Russian annexation of Ukrainian industrial and agricultural wealth, just as Russian annexation of Crimea rewarded putin with critical port city Sebastopol.
Russia simultaneously invaded Kherson and the southern coast of the Sea of Azov to seize a land bridge to Crimea and of course to open the door to take Odessa, long desired warm water port, and isolate what was left of inland Ukraine.
Simply ridiculous to claim that putin was in any way threatened by NATO or western Europe, who had prostrated themselves before Russia with anemic military development, and perhaps more importantly, dependence on Russian fossils.
While putin certainly saw this multi-layered olive branch as weakness, not threat, he used and still uses the strawman of NATO "encirclement" to justify his naked land grab. Sadly, he has many "allies" in the west to spread his disinformation.