[dogma1138]

That only works for services that do not store any sensitive data and employ costumer controller encryption, if your password is used as a cryptographic tool then it’s out of the question to use such mechanism.

[choward]

Then how would you be able to reset your password? All I'm saying is that any service that allows password resets shouldn't have passwords at all.

[vxNsr]

Whatsapp has figured out a solution to this problem. i.e. what is your Whatsapp password?

[PappaPatat]

Your telephone number. So instead of something you know (password), they use something you have (phone).