You use local user template accounts when you need different types of templates. Each template can define a different set of permissions appropriate for the group of users who use that template. These templates are defined locally on the Services Router and referenced by the TACACS+ and RADIUS authentication servers.
When you configure local user templates and a user logs in, JUNOS software with enhanced services issues a request to the authentication server to authenticate the user's login name. If a user is authenticated, the server returns the local username to the device, which then determines whether a local username is specified for that login name (local-username for TACACS+, Juniper-Local-User for RADIUS). If so, the device selects the appropriate local user template locally configured on the device. If a local user template does not exist for the authenticated user, the device defaults to the remote template.
For more information, see Setting Up Template Accounts.