Arnold Friend wants to appeal to the popular sensibility that he sees in Connie. By pulling up to her home and honking in a manner that reflects a sense of being familiar, he figures two things will happen. The first is that Connie will think that "a friend" of hers has arrived to pick her up or to hang out with her. The second is that she will come to the front to see who it is because he understands that she is very much driven by the idea that being popular and being seen is of vital important to her. Arnold is regrettably right on both fronts. He knows that she is home alone. By pulling up and honking the horn, she is able to respond affirmatively, as if one of her friends has come to hang with her. Arnold's intent is to tap into the adolescent sensibility to be seen and to see. He figures that pulling up and honking four times as if he knows her will enable him to open up a line of communication with her. The significance here is that Arnold recognizes Connie's personality and temperament fairly quickly and understands how to entice her. Regrettably for her, he is right. In pulling up and honking and then through talking with her in a manner that seeks to establish rapport through "being cool," the stage for the horrific turn of events is set.