Ha ha. You couldn’t find an easier target to pick on than a 15+ year old design by a grad student with the implementation largely done by undergrad CS classes?

Here’s a more direct link to the documentation in question http://argouml-stats.tigris.org/documentation/manual-0.24/ch10s09.html#d0e7682 so that your readers can see the graphic in context.
(It’s also version frozen so it won’t change if the manual gets modified).

You’ll notice directly under the graphic the text, “ArgoUML provides a single design goal, Unspecified, with its slider set by default to priority 1. However it contains no critics and so has no effect.” In other words, this is a stub. Yes, users shouldn’t be exposed to a stub that adds on value, but there are a lot more important problems to fix.

The ArgoUML interface is sucky in a lot of ways, but the good thing is that it sucks less all the time. Fixing things like getting Undo to work will provide a much greater benefit to users than changing a goofy dialog box though…