The problem follows:
When the player choose to click play on the WoW patcher (after the patch is fully done), it doesn't pop up the WoW client. It will only open WoW when you delete the "Launcher.wtf" file in your wtf folder. But as result, the patcher thinks he isn't done downloading everything, every time when you try to delete this file. The patcher will re-download the "Launcher.wtf" file and again, it won't start the WoW client. The only way to get passed the launcher is to delete this file, every (freaking) time.
My question to Blizzard is: Can you tell us how to fix this or can you change your freaking annoying patch for us? Because we have this problem for a while and it has been posted for many times, I'll hope you hear our call, Blizzard.