A chart can be perfectly formatted and still be wrong. In accounting and operational reporting, the most common cause is not the visual—it is the grain of the data underneath it.
Grain means what one row represents. One row might be an invoice, an invoice line, a payment, an account balance at a reporting date, a CRM deal, or a single activity. Those are different business events.
When they are treated as interchangeable, totals multiply, dates lose their meaning, and filters answer a different question from the one in the chart title.
Start with the business question
Before choosing a table or chart, write the question in one sentence:
