Have I Really Reached You?

Why do people say on their voicemail/answering machine message “You have reached ______”?  That doesn’t seem like an accurate statement.  If I had reached you I wouldn’t have to leave a message.  In fact, I am leaving you a message because I couldn’t reach you.  You know what?  Forget it.  I’m not leaving a message.  I’ll just keep calling you over and over until I reach you.