The dialog shown when running xfce4-panel on a new account is surprising to novice users, and one bad click can ruin the first impression of XFCE usability. Jonathan Dowland described this well in a report on the Debian tracker at https://bugs.debian.org/856309:

-- begin quote --

Upon starting XFCE (really xfce4-panel) for the first time, You receive a
prompt like

    Welcome to the first start of the panel
    Choose below which setup you want for the first startup.
                      [Use default config] [One empty panel]

I believe this prompt is misguided. If you are the type of user who wants the
second option, a blank panel, you can quite easily get there from the default
one: either edit it in the UI tools and remove all the widgets (and panels)
that you won't want, or monkey with the settings files in the background.

If you aren't, there's a chance you are a novice user, or at least unfamiliar
with XFCE and its internals. Trying to get from the blank panel to a useful
one, or even the default, is very hard. (even figuring out which config files
to blast away and whether to do that in an open session or not is challenging).

Therefore for some users, selecting "one empty panel" is a dangerous thing to
do, leaving you with a mostly useless session and no easy way to get back to a
useful one.

This would be mitigated a bit if there was a "restore to defaults" option in
the panel configuration, but there isn't. The user is also being prompted by
(at least) ClipIt's "Save history" question so the initial session can be a bit
overwhelming.

I think the prompt should simply be removed and the default config be used by
default.

-- end quote --

I fully agree with him and think that this should not only be addressed in Debian, but by XFCE in general.

Please consider removing this dialog in favor of the default config being the default.