I've just scanned over a few Putin news articles from 2021. I thought I'd be able to see him making veiled threats if he knew he was going to invade.
Yet, in June Biden and Putin released a joint
statement saying, "...the United States and Russia have demonstrated that, even in periods of tension, they are able to make progress on our shared goals of ensuring predictability in the strategic sphere, reducing the risk of armed conflicts and the threat of nuclear war."
That same month an an in-depth
interview with an American journalist Putin said, "...if you ask my opinion now, I am telling you what it is. The most important value in international affairs is predictability and stability."
I just read a few articles, but to me it doesn't look as if Putin has been planning this war for a long time... Maybe he isn't really so strategic and analytical, but rather impulsive and emotional?