What Are the Russian End Goals?

I think you have to understand that when countries think they're facing an existential threat and they become desperate, they're willing to roll the dice. The best example of this is when Japan attacked the United States of Pearl Harbor on December 7, 1941. When great powers especially are in desperate straits, they tend to use extreme measures to try to rescue the situation. So I think what happened on February 24th is that Putin concluded that he really had no choice if he was going to prevent the West from turning Ukraine into a Western ball war on Russia's borders than to attack  and that he did.