[Azure AD] Device identity - Overview clarification

Author: MicrosoftGuyJFlo

articles/active-directory/devices/overview.md

@@ -57,7 +57,10 @@ Devices in Azure AD can be managed using Mobile Device Management (MDM) tools li
 
 ## Resource access
 
-Registering and joining give your users Seamless Sign-on (SSO) to cloud resources and administrators the ability to apply Conditional Access policies to those resources. 
+Registering and joining devices to Azure AD gives your users Seamless Sign-on (SSO) to cloud resources. This process also allows administrators the ability to apply Conditional Access policies to resources based on the device they are accessed from. 
+
+> [!NOTE]
+> Device-based Conditional Access policies require either hybrid Azure AD joined devices or compliant Azure AD joined or Azure AD registered devices.
 
 Devices that are Azure AD joined or hybrid Azure AD joined benefit from SSO to your organization's on-premises resources as well as cloud resources. More information can be found in the article, [How SSO to on-premises resources works on Azure AD joined devices](azuread-join-sso.md).