Reporting
If the model cannot hold the question, the dashboard will lie.
A chart cannot invent a link the records do not have. Fix the model, then draw the number.
Question
The sentence the report must answer. If you cannot say it without the chart, the chart is early.
Grain
One row means one deal, one contact, or one brand. Mixing them in one table double-counts.
Association
The link the question needs. Revenue by brand needs a brand on the deal, or a path to one.
An owner for the number
The person who says whether the report is still true after a property changes. A dashboard with no owner drifts, and then two teams quote two versions.
What a formula cannot do
Stand in for a missing association. If the brand is not on the deal, no calculated property will put it there.