There are cases when you want to trigger a failure directly. This can happen for multiple reasons, even if there are disadvantages in doing so since, when you trigger the failure, the playbook will be brutally interrupted and this could leave your machine in an inconsistent state if you are not careful. One case where I have seen it work very well is when you are running a non-idempotent playbook (for instance, building a newer version of an application) and you need a variable (for instance, the version/branch to deploy) set. In this case, you can check that the expected variable is correctly configured before starting to run the operations to ensure that everything will work as expected later on.

Let's put the following code in playbooks/maven_build.yaml:

- hosts: all
  tasks: 
    - name: Ensure the tag variable is properly set
      fail: 'The version...