it's been my experience that people can change, but it takes a rather large incentive...a sincere desire to change is hardly ever the cause of change.
making a particular behavior rewarding will cause that behavior to be repeated...making another behavior result in a punishment will make that behavior less appealing in the future.
look at our own little problem, where a conman has gotten away with brazen grifting his entire life, and it only emboldened him to grift his way to treason...
putin has gotten away with being a bully his entire career, and it has only emboldened him. make his behavior painful, and he'll eventually quit doing it...make it VERY painful, and he'll stop doing it a lot sooner.
are the sanctions painful enough to have a result in the near future? i sure hope so, seems like the most action the Ukrainian's allies are willing to take.