Do you know that English has its own tune and voice modulation? Americans, the British and the Aussies speak the same language but the moment you will try to listen it properly you will find huge difference in their ascent and the way they pronounce different words. Here comes the role of ascent neutralization into picture where you don't speak British or American but you just shed your own local tone and make your ascent clear and understandable by English speakers of the World.