What is the effect of BPM Task Aggregation setting "All Stages"?

In BPM Worklist —> Administration —> Task Configuration —> [any task, e.g. ReqApproval] —> Configuration, there is a Task Aggregation setting with four options: None, Once per task, Once per stage, and All Stages. The documentation linked below contains descriptions for the first three options, but there is no mention of the last, All Stages. I can't find this setting documented anywhere. What does it do?

https://docs.oracle.com/en/cloud/saas/financials/26a/fafcf/aggregate-tasks-to-minimize-the-number-of-notifications-to-send.html