No, but people often use the same password for different services. Changing passwords regularly can cut off attacker access in the event of an undetected compromise.
Well, those people would probably simple cycle through their passwords, or append an increasing counter. So regular changes do not protect the security, but annoys people that are using generated passwords that are completely unique for each and every service.
Increasing the counter at the end is obviously weak when you find that "password46" is not working anymore so you try "...47".
However if someone steals a whole password database with a million passwords, chances are they just automate the login attempts and subsequent nefarious actions. They might not try to figure out anyone's naive password scheme if they get thousands of successful logins the easy way!?
I'm saying this because I've heard your reasoning before, and of course I've been staring at the keyboard when trying to change one of my passwords, wondering just how clever I need to be right there.
