It is rude to leave someone hanging.
Geoffrey's girlfriend walks into the room wearing a new dress and asks him what he thinks.
Geoffrey wants to convey how beautiful he thinks she is in the dress.
Geoffrey tells her that is the most beautiful dress he has ever seen her wear.
Geoffrey feigns a shocked silence staring at her without answering, hoping she interprets it as him being thunderstruck.
Geoffrey's girlfriend blushes and walks over and kisses him on the cheek.
Geoffrey's girlfriend assumes he is being rude, and storms out of the house angry at him.