Lets assume I go with AWS/EKS, kubernetes deploy, as described in this tutorial. Why Do I need to have a Docker registry?
The way I understand (probably wrong): After the Jenkins Pipeline is run, the image is pushed on to repository (S3 or similar), and then from there deployed.
Why Docker registry?
As I have went through almost complete documentation, in one place I found the WHY.
In short, all starts with Github push. We can Use Jenkins, and Jenkins produces deb package and stores it in S3.
We could also use Kubernetes. It also starts with Github push, but in this case we have Dockerhub, which listens to a Github, and then makes an image.
The rest with Spinnaker is same in both cases.