WP Fb Messenger - no. of notifications

[VivekRabara]

On live tile, fb messenger always shows notification count as 1. Am I getting wrong with this notification system or is it so? Either it should work as whats app or it should display notification count based on no. of people/group it comes from.

 

[RobinPaul]

It has been designed like the by Facebook.

 

[VivekRabara]

Strange!! It shouldn't be like this. Can anyone explain?