It seems to do nothing.
It seems to do nothing.
It most likely will always show the launcher if you are still downloading such.
But if you really don't know, it makes it go straight from the icon you hit, to WoW. No launcher.
which is something blizz recommends against doing for security reasons.
When you go to your WoW folder you see a Launcher.exe file and a wow.exe file.
Launcher.exe starts (surprisingly) the Launcher, that will give the latest news, download and install patches straight away. wow.exe just starts WoW (omg, can it be true?! :O) and will bypass the Launcher.
If you by any chance have that file as a shortcut on your desktop, it will never show the launcher, even if you check the box. If you have the 'standard' shortcut (created by WoW upon installation) the launcher will start when said box is checked.
My guess is, that you have a shortcut that refers to the wow.exe file, instead of the 'standard start wow now' file.
Pilot: We've got a little situation ladies and gentlemen.
Samuel: What seems to be the problem, Mr. pilot, sir?
Pilot: There are snakes on the plane.
Samuel: FFFFFFUUUUUU