aral, 
On #GNOME, you have this really useful app called Settings where you can, well, set your system Settings. So far, so good.
So then one day, it stops launching. Oops! So you go into terminal to try and launch it to see if there is any debug output…
settings
Unknown command.
Oh, why? Because Settings app’s binary isn’t called settings, it’s called gnome-control-center.
But of course you already knew that because you can read minds.
(Raised similar issues before, they don’t get the problem.)