If you’re doing things properly, you’ll know your Microsoft account password or have it in a password manager (and maybe have other account recovery options available like getting a password reset email etc.), and have a separate password for the PC you’re locked out of, which would be the thing you’d forgotten. If someone isn’t computer-literate, it’s totally plausible that they’d forget both passwords, have no password manager, and not have set up a recovery email address, and they’d lose all their data if they couldn’t get into their machine.