Customers can ask SAP to „clone“ instances from production to test (or other constellations). Many customers do this for regression tests, alignments, and other reasons, like adding additional instances (for training, e.g.). During the process of cloning data, agents and background jobs are copied.
The Personal Data Health Check ensures that you gain full insight on notifications coming from a newly cloned instance (potentially being copied from the master). Based on this you decide which notification should be send out to which recipient. By this you can cure side effects from cloning, like sending out notifications including personal data to recipients which do not need to know or do not have the authorization to receive this info.