Paid, Organic, and Unknown Sources
What each bucket contains, and why unknown is not a failure.
Paid
An enquiry Ghost can tie to advertising you paid for. These are the only enquiries that belong in a return-on-ad-spend calculation, which is why Ghost is careful about what it puts here.
Organic
An enquiry from a source you did not pay for in this period — a search result, a map listing, a referral, a returning customer. Real, valuable, and not part of ad spend.
Unknown
Ghost has the enquiry but no evidence of where it came from. The enquiry is counted everywhere it should be counted; only its source is missing.
Why unknown matters for your numbers
Unknown enquiries are excluded from paid performance, so a large unknown bucket makes advertising look worse than it is. That is the honest direction to be wrong in — crediting ads with enquiries they may not have produced would overstate the thing you are using to decide a budget.
The way to shrink it is better source information, not a different rule. Start with Review Tracking.