ANY WAR IS UNPREDICTABLE IN ITS OUTCOME. This has always been the case. Even when fighting against clearly weaker opponents. Remember the US troop deployment in Afghanistan. At first, the prospects were rosy — everything was on the Americans' side (they had the most modern weapons, equipment, and technology), but it ended in a shameful withdrawal of troops. Well, what was the risk assessment, and what can we say about it?
Remember Israel's attack on Iran. and the same thing happened — weapons, equipment, the most modern aircraft and missiles, but they got beaten. So they had to complain to the Americans — help us deal with Iran. And risk assessments...
Russia has its own tactics and strategy. Maybe its risk assessment is not so powerful, but even without it, it wins. Although the start of the special military operation was botched. And Russia is fighting the most advanced enemy - NATO, led by the US. Although many are afraid to admit it. And risk assessment did not help NATO. Well, they have their own tactics and strategy. And it is precisely the unpredictability that scares them from sending their troops to Ukraine and starting a war against Russia.
Translated with DeepL.com (free version)