Problem with Email tasks

[Itsik]

I have a specific naming convention for servers, so I can distinguish the server role from the server's name.
All production servers' name starts with a P and test servers start with a T.
I created 3 Email tasks to send alerts for production servers, test servers and all the rest, specifying the serve's role in the email subject. The 3rd task checks if the system name DOES NOT start with a P AND DOES NOT start with a T. The problem is I'm getting 2 emails for each alert, as if the 3rd task's rule always applies. Why is that ?