Member roles in the discord server will be mapped with WordPress role during Single Sign-On (SSO). So whenever a user logs into the WordPress site using their Discord login credentials, user roles will be fetched from the discord server and mapped to the WordPress user role. For Example, Suppose a Discord user logging into your site is already a member of your Discord Server, having specific roles (which differentiate the members having access to different private channels on your server). In that case, you can assign him WordPress roles (subscriber, contributor, author) or custom roles created with some third-party plugin based on his roles on your Discord Server. This feature is accessible on all higher versions of the WordPress Discord Integration plugin, starting with the standard plan.