Most CMS technologies are what we would call a “coupled CMS." The content authoring and content delivery environments are usually part of the same stack. The act of "going live" with new content or a feature is essentially based on the act of marking a true/false in a database field. There are a lot of problems with coupled CMS platforms around security, performance, scalability, and flexibility (you can learn more here.)
For these reasons and many others, Crafter CMS is built as a decoupled CMS. With a decoupled CMS you author content in one system and publish to another separate system. For platforms like Crafter CMS that are decoupled, when correctly implemented, the architecture provides great solutions for the issues mentioned above. That said, nothing is without its challenges. Decoupled systems, by their nature, are typically very scalable and can have many instances all over the world. Security, scalability, and distribution are no longer issues that only concern the Internet’s biggest players like Google and Amazon. Security and distribution impact customer experience, safety and help reduce operating costs. Every brand-conscious and customer-forward organization in the world is focused on these tactical issues.