If Russia is hell bent on absorbing Ukraine it obviously has the resources to do so. It sure looks like a costly, Pyrrhic victory though.
Putin probably didn't anticipate Russian citizens and previously friendly members of Russia's oligarchy speaking out against this war. The international community's swift and united condemnation had to be a little surprising, too. Even Switzerland(!) is peeved enough to be taking sides, and China isn't offering public support either.
Russian dance companies, artists, sports teams, other athletes, celebrities, and super-rich are suddenly persona non grata, with "unvitations" being issued by the score. Gotta be painful.
As many countries have learned the hard way, superior firepower doesn't guarantee victories, much less lasting ones. Winning hearts and minds through bullying firepower? Hasn't worked yet...
Occupying a country that doesn't want you costs both sides plenty in blood and resources. Difference is that the foreign occupiers become exhausted and disenchanted by the process long before the people living there.
A lot of countries - Russia and the US included - repeat this lesson many times over without understanding it.