Obviously, traditional speaking is better than private messages; On the other hand, there is not a speaking history. So I prefer emails because they are written

Obviously, traditional speaking is better than private messages; On the other hand, there is not a speaking history. So I prefer emails because they are written on black and white. For example: someone could ask me something that it is not what he wants or it is not corrent. On traditional speaking, a third person doesn't know who said what. On email, it is all written.