Qt custom plugins install to wrong location?

[shavera]

I ran the most basic variant of the Qt custom plugin, the world clock example.

When I ran make install it installed to:
<QT_ROOT>/5.4/gcc_64/plugins/designer/libworldtimeclockplugin.so

But for Qt Designer to recognize the file, it needs to be installed to
<QT_ROOT>/Tools/QtCreator/bin/plugins/designer

I know I can set the install prefix myself, and get it to install appropriately. But is this indicative of some larger issue? Should documentation be updated? (Documentation should at least include the appropriate install directory if it is to be set manually, I found this through a bit of trial and error in the many 'plugins' folders within the Qt directory system)