A coverage gap is a format, topic or angle an account's audience already responds to elsewhere that the account itself has never posted. It is the difference between what a market rewards and what an account has actually tried.
Naming the gap is only useful once it turns into a scenario — a gap by itself is a description of a market; a scenario is a specific video that closes it.
A gap that never becomes a scenario is just an observation. The point of naming it is the video that closes it, with its own hook and shot list.
A gap is usually found by comparing an account's own post history against the accounts its audience already watches — not a generic industry list — which is why the accounts worth comparing against are the competitor set, chosen carefully.
A common mistake is treating every gap as equally worth filming — a gap the whole competitor set already exploits is a safer bet than one only a single account tried once, and the evidence behind a scenario is what tells the two apart.
A gap can also close on its own: a topic no account was covering last quarter might be crowded by the time a scenario gets filmed, which is why a coverage gap is read against a current competitor set rather than treated as a permanent finding. A gap is worth naming even when an account is not ready to film it yet, since a documented gap survives longer than a memory of noticing one and gives the next planning session a running start instead of a blank page.
Where it comes from
This is Rankfield’s own vocabulary, not a platform metric. The landing page names it directly, as one of the research chores Rankfield runs before a business ever has to film.
Coverage gaps
Read the source: Rankfield — the research chores the landing page lists.
What Rankfield reads
The landing page answers this directly, in its own words:
Your account end to end, your competitors, and the wider market around you: posts, videos, captions, comments, rhythm, what you offer. It watches the videos, not just the numbers under them.