Assume that an information is not needed to be written down unless proven otherwise.
Always implement things when you actually need them, never when you just foresee that you need them.
Ron Jeffries. You Aren't Gonna Need It
YAGNI - You Aren't Gonna Need It: The cost of creating a document may be magnitudes smaller than the cost of maintaining that document. A document providing information that is out-of-date typically inflicts more harm than a document that does not exist.
Therefore documents are liabilities that should be created with due diligence. This starts by finding and naming at least one stakeholder who demands the information in written form. Write documents just-in-time when there is actual demand to have the information in written form.
References
More information on this principle.
