How do the "Request for Activation" and "Request for Deactivation" workflows work?

My requirement is to trigger a custom workflow when a use tries to publish or unpublish the assets through Quick Publish or Manage Publication options.

This can also be managed by adding a customized step in the OOTB workflow that gets triggered on click of those buttons.

My understanding was that "Request for Deactivation" and "Request for Activation" workflows get triggered in these case, but the same is not happening.

Please suggest if I am missing something.

Additional Info:

The "Schedule Deactivation of Assets" workflow is getting triggered on scheduling a deactivation but not the immediate one.