1) His premise that Russia has some recognized right to exercise power over their "Sphere of influence" that includes other souvereign nations. While some poeple, even outside Russia, can agree to that, most of those who matter don't, including China. Even though some may not appreciate that more countries have been joining nato, the right of each nation to make their own decisions about their alliences is seen by most as a higher priority principle. 2) His assertion that the regime in Ukraine is not legitimate after 2013. In 2014, some weight could be given to that argument, but today, it is clear that the population in Ukraine generally recognizes their government. Claiming that it is illegitimate, is similar to naming the ROC the legitimate government in China. 3) Related to (2), the belief that the population of Ukraine would welcome Russian forces as they entered their territories were clearly ill-informed. In reality, Ukraine has been fighting with all the conviction and unity you can expect from a country that values its independence. 4) Putin's apparent belief that his military was strong and capable was similarly mistaken. On paper, Russian forces should be able to overwhelm Ukraine in days or weeeks, based on numbers of troops and materiel. In reality, the organization, morale and logistics/planning of the invasion force was horribly bad. 5) Related to (1): Putin's apparent expectation that Nato would remain completely passive was partly wrong. European nations reacted immediately with shock at the invasion, with military budgets almost instantly give increases that in total was multiple times larger than Russia's total military budget. Also, instead of acting as a deterrent, Putin's aggression has shown neutral neighbours that they need to be members of Nato if they want safety. (Like Finland in Sweden, who used to be very happty to stay neutral). For countries already members of Nato, Russia's aggression also meant that many trading partners realized the danger of being dependent on Russia for strategic resources, particularily oil and gas. If most of the EU is able to become independent of such trade, that will be a huge economic loss for Russia. 6) Related to (3) and (5), the fact that Ukraine was able and willing to defend themselves so valiantly, led to weapon deliveries to Ukraine that I don't think Putin expected.
So in sum, a series of misjudgments by Putin (based on, I think, not receiving realistic information about military and political matters), is now leading Russia into potentially a catastrophic worsening of their situation, both economically, politically and in terms of national security. If they maintain their current trajectory, I anticipate either loss or a very drawn-out conflict in Ukraine with no clear "winner". I predict that Russia will end up isolated from the west, and become in effect a puppet of China.
If so, I'm not sure to what extent India will want to maintain their relatively good relations to Russia either, as India's main competitor (I think) may no longer be the West, but rather China.