Anecdotal but I worked for a non tech company over a decade ago that had a monthly password change policy. When I started at the company my desk wasn't ready the first day so I was seated on the workstation of another employee who was in vacation. First thing I saw was his password on a post it under the keyboard.

I worked at a place that had such policies; it is a national engineering lab. They are owned (mostly, some are joint ventures with universities) by the Department of Energy (who builds and owns America's nukes - they're just leased to the Dept of Defense). While my lab had nothing to do with nukes, some of the other labs made them. So we got many of the same security policies that Los Alamos had. Which meant it took me about 45 minutes to figure out a new password that wasn't too close to one I previously used, nor did it have a 3+ letter word in any language (I have no clue which languages they tracked) forwards or backwards.