Private SSO is sometimes not enough.
It is therefore possible to strengthen authentication security by using a feature called "forced SSO".
Prerequisite: the forced SSO option is only available to console users.
When enabled, this option disables the basic email/password login.
This means that users can't use their usual login credentials or reset their password if they're in an environment where SSO is mandatory.
If you'd like to find out more about SSO single sign-on, see this article: What is SSO single sign-on?