Why is kube-controller-manager implemented as pull instead of push?

svenmathijssen

Question about 2 => Kubernetes Architecture => API flow. An explanation is given of how the kube-controller-manager performs its work. I'm a little curious as to why the process seems to be implemented as a control loop (i.e. pull) instead of push? I would think a setup where the API server pushes changes to the kube-controller-manager feels more logical since it is aware of any change requests that come in.

What triggered me also was the fact that in the example, it is clear tha the response for creation of a deployment returns almost instantly, suggesting that either there is only a small amount of time that passes before each control loop is executed, or the request is processed asynchronously in the background.

Thanks in advance!