It has to do with the way you enter the chatroom. If you click on the chat link in the general menu, then it will not count you when you enter the room (something I have to fix). Also, if you have another window open for YWS, it won't count you either. It's a very fickle count...
As the notifications drift in I stop and wonder. Why do they take so long? Do they have adventures we don't know about? I bet they do. When they come I will ask myself. What amazing adventure has this straggling notification been on? How far did it travel, and why didn't it take me? — TypoWithoutCoffee