Often, you develop a website to be installed and used once, by one organization. But sometimes, for larger organizations, you need to develop a series of websites that are very similar. This case is very common in big institutions with independent departments or branches, such as:
As Drupal 8 "relies" on a Configuration Management (CM) system, one of its cool improvements is restoring a Drupal 8 site from an existing configuration instead of only a database dump. This means that you can do a brand new Drupal installation and replicate an existing configuration on your new fresh database!
Drupal 8 Configuration Management (CM) is a "killer feature" for a web Content Management System (CMS). When setting up a Drupal site, we spend a lot of time on site configuration: Roles, Permissions, Content Types, Menus, Vocabularies, etc. In most CMS's, all these changes are stored in their databases, making it hard to deploy, track, reuse and rollback important changes.