Twelve-factor applications are an excellent start toward building applications that operate in the cloud, but to build cloud-native applications that truly thrive in the cloud, you need to look beyond the 12 factors.
My challenge to you is this: evaluate your existing applications against the guidelines set forth in this book and start planning what it would take to get them to run in a cloud. All other benefits aside, eventually, everything is going to be cloud-based the way everything today runs on virtualization.
When you’re building a new application, force a decision as to why you should not build your application in a cloud-native way.
Embrace continuous integration, continuous delivery, and the production of applications designed to thrive in the cloud, and you will reap rewards far and above just what you get from a cloud-native world.