Separate records from inference
Cost, leads, deals, and revenue are records; contribution across touchpoints is a model with assumptions.
Show the denominator
CPL without lead count or ROAS without complete spend and revenue misleads. Show unavailable when the basis is missing.
Audit source quality
Test UTMs, webhooks, deduplication, and identity linking before discussing a dashboard.
Takeaway
A good system does not decorate gaps; it exposes them and gives the team a practical next step.