Manager: We need to ensure people aren't using similar passwords on reset, but we can't store the password unhashed.
Developer: Similar passwords? Or Same passwords. Similar is hard.
M: Similar. Can't let people be lazy with their passwords.
D: Well, if we really have to do it, I guess we could store a bunch of hashed variations of the password, but...
M: Good! Let's do that.
D: ...but that could be a massive amount of space for long passwords.
M: Okay, we'll just enforce short passwords then.
D: ...doesn't that more than negate all the benefit of preventing similar passwords when rotating them?
M: Doesn't matter, the CEO said he wants this. Hop to it!
Developer laments the stupidity of their life
Developer: Similar passwords? Or Same passwords. Similar is hard.
M: Similar. Can't let people be lazy with their passwords.
D: Well, if we really have to do it, I guess we could store a bunch of hashed variations of the password, but...
M: Good! Let's do that.
D: ...but that could be a massive amount of space for long passwords.
M: Okay, we'll just enforce short passwords then.
D: ...doesn't that more than negate all the benefit of preventing similar passwords when rotating them?
M: Doesn't matter, the CEO said he wants this. Hop to it!
Developer laments the stupidity of their life