Ukraine may have studied up on the previous time the Soviet Union thought invading an undermanned and underequipped such as Finland would be an easy mark. The Fins promptly bloodied their nose and inflicted heavier losses in everything from aircraft to tanks to personnel. Probably saw the rise of one of the deadliest snipers in history by all accounts. Russia made an irreversible and costly blunder invading Ukraine. It's probably a good thing NATO finally decided to join Finland.