One definition, everywhere.
WHAT THE PROBLEM IS
The same metric calculated differently in different places, producing conflicting numbers.
WHAT THAT CAUSES
Meetings spent arguing about which figure is right, rather than what to do.
WHAT CAUSES IT
Definitions living in individual reports and queries No agreement on what a term means Filters applied inconsistently
WHAT TO ESTABLISH
A single definition per metric, agreed and documented.
WHAT TO DOCUMENT FOR EACH
The plain-language definition The exact calculation What is included and excluded The grain it applies at Who owns it
WHY EXCLUSIONS SPECIFICALLY
Most disputes are about what was excluded: test accounts, refunds, internal usage.
WHAT A SEMANTIC LAYER PROVIDES
Metric definitions held in one place, used by every tool.
WHY THAT MATTERS
Definitions cannot drift between reports.
WHAT TO BUILD WITHOUT ONE
Shared views or models, with definitions in the warehouse rather than in reports.
WHAT TO NEVER ALLOW
Metrics redefined in a spreadsheet downstream.
WHAT TO REVIEW
Whether reports agree, deliberately and periodically.
