In the mid 1990s it was all about modems and dialups. 'Dial-Up-Networking' often forced people to type in passwords even after it was told to remember them. Discovering why required an investigation of files and registry and a meticulous tech support session. Not surprisingly most people just shrugged it off and kept typing passwords.
But CAPSLOCK kept tripping them (I remove the keycap and put black tape over the switch). Be they neophytes or drunks, we were getting 20-50 cant-log-in calls a day with this simple remedy. And it seemed they didn't learn, but that was just a stream of new people. I had decided * characters masking the password field was evil and inhuman. This may not sound like a big number but some of the calls got you out of bed at 3am and aside from that everything was going smoothly.
Our Ascend MAXes made RADIUS calls to assign connection profiles from user/pw pairs. Our usernames were already case insensitive. I delved into the RADIUS source code and added a step to the password process: If "mYpASSWORD123" failed, it would immediately flip the case and try "MyPassword123" and let them in if it worked, logging the username as 'caps-corrected'. Within a month we had over 1000 corrections. This was not like ignoring case which is definitely bad practice. The case flip trick only decreased alpha password space by half.