VERIFIED SOLUTION i
Designer provides functionality to use Message Signal as Conditional Logic. Message signal are associated on condition attached with messages in Content Author. The message signal can be later used in Designer. It was observed that for message signal which was true, Designer editor shows "False branch" enabled.
Tthe messages are not utilized by Designer, it's only during production that the messages are used, so only then will the message be placed, and the message signal activated.
ResolutionUPDATED: May 16, 2017
This is a expected behaviour. During 'Advance Preview' correct results can be observed.