Today an adventurous Revit user thought he'd use Purge Unused unsolicted. This during a day long excursion into the workset environment with fourteen concurrent users. We discovered this when I gave the gang the task of sketching some interior partitions on "their" floors and we were a bit surprised to find only three walls in the project. So I casually commented that could only happen if someone chose to delete them or use Purge Unused. At this point one of our gang volunteered, "oh I did that!". Much laughter and conversation ensued between the rest of us.
To fix the problem of missing stuff, we used Transfer Project Standards. That's when bumped into the next issue or gotcha.
If you create new elements in your local file while someone else uses Purge Unused in their local and they STC (Save to Central) first, guess what happens to your stuff.
It goes away! That's what!
Logical and consistent with the existing relationship of local files and central file. However it seems to me that Purge Unused ought to be a bit "smarter" or disabled except under special circumstances like working in a central with no other users or no other uses while in a local perhaps.
It was a first for me, nobody has used Purge Unused before without first asking about the feature. Remaining "half full" it's better that it happened during a training session than on a live project!