I sometimes consider the number of man-hours wasted every year by companies (such as Amazon and Dropbox) that repeatedly offer to convert passwords to passkeys, despite having already been declined (once, or even dozens or hundreds of times).

This reminds me of the number of man-hours wasted on logging in into Microsoft accounts - bonus points for "No, this app only" being hit after the session timeout of the login session so you have to log in _again_. (instead of being able to make that decision any time you like, because, you know, you've already authenticated yourself)