According to my back-of-the-envelope calculation just now, approximately 15% of all calls to the Service Desk are password related. In my experience about 95% of password issues are the result of user error. They mess up typing their password and get their account locked, misremember what they changed it to, or flat out forget what it was.
We have self-service password reset facilities in place, and these are regularly communicated to the users. It makes no difference. We didn't get a significant drop in password calls when it was implemented (though I would fact-check that), and hardly anyone seems to use it.
We now have a new secure system where the only way to get a password reset is to use the self-service facility, so maybe the idea will start permeating through the user base. But not all staff use this new secure system.
What is it about people and their passwords? I haven't had to have my password reset more than twice in my 25-year career in IT. About the same rate as I forget my security pass.