Can not delete a directory under plugins

When you have a directory under the $ARTIFACTRY_HOME/etc/plugins, in case the directory is not empty, once the entire (not-empty) directory is removed the following is shows in the artifactory.log:

2017-06-29 12:10:07,596 [Thread-5] [ERROR] (o.a.c.c.w.FileWatchingManager:97) - Fatal error can't synchronize between Artifactory Config files

The directory is deleted, however once the Artifactory instance is restarted the directory is back again with the entire content.

A workaround is to delete the entire directory will be to first remove the content, then remove the empty directory (on the primary).