“the sanctions failed in one crucial way. The fact that Moscow was blindsided by them suggests it grossly underestimated the severity of the penalties it would face. Although the U.S. and its allies had developed an extensive menu of possible sanctions before the invasion, they never reached consensus on how far they were willing to go. They left Putin to divine the meaning of “the most severe sanctions that have ever been imposed,” and Putin—as he so often did—read Western ambiguity as weakness.
If Biden and other world leaders had committed ahead of time to the actions they would eventually take, they might have had a much better chance of staving off Putin’s invasion. Deterrence can’t work if your adversary underestimates your ability or willingness to act. Putin never saw the sanctions coming—and that was precisely the problem.”
https://www.yahoo.com/news/sanctions-antibiotics-160000035.html