Around a year ago, I was convinced Putin wouldn't invade Ukraine because the West would find new energy sources, starving Russia of key income, and Sweden and Finland would join NATO. Not only that, Russia is now confirmed to be the the junior partner in its relationship with China.
In hindsight, I do buy into the argument that NATO grew too much to the east, and there would have been wisdom in creating an "DMZ" between NATO and Russia. The growth of NATO left Putin feeling trapped. It would have been better to slowly move Western resource sources to better sources and friendlier countries.