The Kubernetes Operators book (http://shop.oreilly.com/product/0636920234357.do - chapter 7) states the following:

While the Helm and Ansible Operators can be created quickly and easily, their functionality is ultimately limited by those underlying technologies. Advanced use cases, such as those that involve dynamically reacting to specific changes in the application or the cluster as a whole, require a more flexible solution.

The above paragraph is comparing operators written in Helm or Ansible with those written in code such as golang.

I believe the operator introduction documentation provides some examples of advanced use cases where Helm or Ansible operators will be too limited:

Operator automation to alert and act on failure, backup, or reconfigure.

...

Operators can make it easy to periodically back up application state and recover previous state from the backup.

What are all of the advanced use cases where Helm or Ansible operators will be too limited?