Work is scoped against what the sources can actually support. Rows that cannot be verified are separated from rows that failed verification. Sometimes the honest finding is that no such audience exists, and that gets said.
Count reconciliation after build
Re-running the figure against the finished extract, so the two cannot drift apart unnoticed.
Audience scoping
We turn a description of who you want to reach into criteria that can actually be counted.
Coverage reporting
Stating what matched, what did not, and what could not be checked, as three separate numbers rather than one.
Start with a single segment and judge the rest on it.