Russian forces currently occupy something like 16-18% of Ukrainian territory.If you think losing half your country (or 25%) is a win, then I hope your country won't win in a war
As for Finland, they traded roughly 9% of their territory for independence. It paid off, as Finland is today considered one of the best places to live in the World. Stalin's invasion of Finland was disastrous; not only did the USSR lose almost a quarter million men but the underwhelming performance of the Red Army in the 1940 war, was a key factor that convinced Hitler that he could successfully invade and defeat the USSR, if he moved swiftly. He invaded in 1941 and the rest is history.