What is the usecase of Purge Days while creating a workflow? Is it means we can remove that workflow after purge days?

What is the usecase of Purge Days while creating a workflow? Is it means we can remove that workflow after purge days ?

As of now, this functionality is not used (not working state) however the use case of purge days is after the completion of purge days duration from the creation day of workflow will be removed / deletion after purge days cc: @naveen.gupta