Hello Dave,
Thank you for posting your concern in Microsoft community and welcome to the Windows 10 Family.
Please consider the following scenarios in which the picture sign-on option will not be available.
Scenario 1: If you have a local user account without Password, you may not get the Picture password and Pin appeared under Sign-in option, or these 2 options are greyed out.
Scenario 2: The computer is joined in the Domain, Both local account and Domain account has the PIN sign-in option grey out.
Group policy as below control this settings, you have to enable it to get this option worked again. Please follow below.
- Press Windows key + R from keyboard and type in gpedit.msc to open Group Policy.
- Navigate to the following path:
Computer Configuration\Administrative Templates\System\Logon
and select Turn on pin sign-in
Hope the above information was helpful. If you need further assistance, please do let us know and we would be happy to help you further.
Thank You.