Deskbar behaviour

When I have just one instance of a program open and/or the program in question only has one window open, why am I presented with a menu when I click on a running program in the Deskbar? In this situation, the program being clicked on should instantly be brought to the foreground and unminimized without having to select it from the sub-menu because the other options (Hide All, Show All and Close All) don't apply. The sub-menu should only appear when multiple instances of an app are running.

Is this a bug or am I missing something?