Idea Summary
Workflows are currently purged as per the blog post https://blogs.oracle.com/apex/post/archiving-human-tasks-and-workflows-in-apex-241

This limitiation makes workflow unusable in a lot of scenarios as while you could do custom reporting on workflow activities, the workflow diagram would no longer render the historic workflow.

There is no such limitation in workflow in a lot of other workflow engines including EBS.

Use Case
Some specific cases we have is that cases are opened, closed and then may need to be re-opened on appeal.  Users would need to look at the history in the same format they could pre-archive purge.  e.g. using the workflow diagram.  This would no longer be possible and the UX would be totally different and it would be diffficult to show complex workflows in reports.  

This would apply to any use case or historic workflow.

Preferred Solution (Optional)
The purge days for workflows should be optional.