Information that is not in a document is information for the reader as well. When it is not explained why it is absent, an assumption takes its place, and that assumption is not under the organisation's control.
A gap is not neutral
A field that has not been filled in raises in the reader the question "is there no information, was it not given, or was it forgotten". The consequences of the three possibilities differ greatly from one another.
A deliberate omission is explained
It can be stated in a short note that a piece of information has not been given on grounds of confidentiality or scope. This note removes the possibility of negligence altogether.
Information that is not in the source is not added
A translation cannot complete a piece of information that is absent from the source document. The omission belongs to the source and is resolved there.
Illegible fields are marked
In scanned documents a section that cannot be made out is not silently skipped. Stating that it could not be read protects the reliability of the document.
A missing page is the gravest defect
The complete absence of a page damages the trust placed in the whole of the document. Preserving the page numbers reduces this risk.
When an abbreviation is not explained, information is lost
An abbreviation the reader does not know makes that sentence effectively unreadable. Spelling it out where it first occurs is enough.
A lack of context is an omission too
A piece of background information that is perfectly obvious inside the organisation does not exist at all for someone reading from outside. An introduction of one sentence closes this gap.
Counter-view: explaining everything bloats the text
It is true that excessive explanation will weigh the document down. The criterion is this: only the information the reader could not possibly know is explained; not every detail known inside the organisation.
Which information is missing can be measured
The questions that come from the counterparty show exactly which information was left out. When these questions are recorded, the next document is more complete.
Templates reduce omissions
A template whose mandatory fields have been defined makes the skipped information visible at the filling-in stage.
An omission has a chain effect
Information left out of one document makes the other documents that refer to it ambiguous as well. Review as a set catches this effect.
Completing it afterwards leaves a trace
Completing an incomplete document afterwards leaves the impression that the first submission was careless. It is preferable for the first form to be complete.
Confidentiality is a legitimate ground
Not sharing a piece of information may rest on a commercial or legal ground. Stating the ground makes the decision defensible.
A checklist is used
Listing the mandatory fields by type of document allows the omission to be noticed before delivery.
An omission is closed at a high price afterwards
Completing what is missing in a document that has been delivered sets back not only that document but also the process of the side that received it. The queue for re-examination has to be waited out, and the time that was meant to be gained is paid back with interest.
Takeaway
Missing information does not stay silent; it is filled in by the reader's assumption. Explaining deliberate omissions in a short note, marking illegible fields, defining the mandatory fields with a template and recording the questions that come in; these four prevent the assumption from working against the organisation.