I have a job that allows parallel runs which frequently leads to a number of workspaces being creted.

After running it a few times I have the following file structure:

jenkins-home/jobs/job1/
workspace
workspace@2
workspace@3
workspace@4

If I run "Wipe Out Workspace" it seems as if Jenkins chooses a random directory of the 4 to wipe out (possibly based on which one was used last). So sometimes it will remove the "workspace" directory, and leave the other 3 and sometimes it will remove one of the others (like workspace@2). It never seems to remove all of them though.