Further on this, here is some explanation as regards the terminology, this time in a Bugzilla ticket:https://bugzilla.gnome.org/show_bug.cgi?id=598690
"Now for a thorough explanation of why we currently have these three options
- Safely remove drive
for a normal USB stick or USB card reader. It seems excessive.
Actually it wasn't always like this. Before bug 597864, we used to collapse
"Eject" and "Safely Remove Drive" into just "Eject" (with the semantics of
first doing "Eject", then "Safely Remove Drive") if it looked like the drive
wasn't automatically capable of physically ejecting the media (e.g. an optical
drive or a zip drive). Then the user only had two options
which seemed a bit more reasonable. Still, for optical drives connected via USB
we had all three options since, well, ejecting the media is not the same as
preparing the device for removal. And we still had that pesky unmount option.
But then bug 597864 roared it's head. The problem, in a nutshell, is that we
don't know if the device is external or internal (see the bug and the
associated fd.o bug for more discussion). So we can't just automatically hide
the "Safely Remove Drive" feature behind "Eject".
Long-term it might (or might not) be nice to have a "Safely Remove Hardware"
facility in the core desktop shell (that would also work for other kinds of
hardware needing this treatment) but that's just not how things work right now.
We could also nuke the "Unmount" option and just tell people to use a terminal
instead for doing that (or Palimpsest). I don't know if that's screwing over
existing users too much though (I'm personally fine with it)."
I hope this helps?