Models that are deleted are moved to the deleted tab and remain there until:
(1) they are restored by pressing the Restore (undelete) option,
(2) they are permanently deleted by pressing the Delete option,
or (3) some period of time has elapsed and the projects are permanently deleted.
Permanently deleted models do not count against the workgroup license models limit.
Warning: Make sure that you really intend to permanently delete your project(s) as this action can't be reversed. Before permanently deleting a model, you might want to download it first, just in case you want to upload it back into a workgroup later.