Persistence is tightly related to positivity. Persistent information is explicitly represented, stated. It is not inferred from lacks of statements: it is localized.
Whether or not the information is indeed meant to be maintained, this property is valuable. This is slightly paradoxical indeed: information is meaning (as opposed to plain data), and meaning implies discrimination, negativity (see Hegel). Nevertheless, this discrimination involves somebody's responsibility. Representing the information gives a support to make this involvement explicit and trackable.
However, communications should be clearly distinguished from documentation. It is easy and frequent to make the confusion (e.g. blinking new labels in web pages). This confusion commonly leads to one-way communication, i.e. via closed documents, which are produced and consumed.
Documentation, even if contextual, is typically more descriptive (objective) whereas communications should be more argumentative (contractual).