Template:Endflatlist is a very simple template. It consist of </div> which is the closing tag for Template:Flatlist which has this content:
<div class="horizontal">
Look at how it displays on Wikinfo:
http://wikinfo.org/index.php/Template:Endflatlist
and on Wikipedia:
http://en.wikipedia.org/wiki/Template:Endflatlist
I'm sure there is a very simple explanation, but what is it? I should add that the templates don't work as you may see from the respective talk pages on Wikinfo.
Fred