Language might not have entirely escaped its origins. Since you can be understood even when you are not well-spoken, what is the point of being well-spoken at all? Perhaps speaking well is still, in part, a form of sexual display. By being well spoken I show not only that I am an intelligent, clued-in member of the tribe but also that I am likely to be a successful partner and helpful mate.
You Are Not a Gadget (2010)