I should have been a little more clear here. I guess I thought if one Qube is going to provide other Qubes some kind of service, you probably want it to be running, at least as long as you typically run the Qube(s) who receives said services. And you may want to have that Qube a little more discreet than the Qubes you typically work in. In a more conventional OS like Windows, if you are trying to provide some kind of service (like an always on antivirus) I think you would therefore run that service provider (in this case just AV software) “in the background” so it doesn’t really clutter up your operations but is still working.