While building a custom table in the Report Editor, a practitioner finds that the Return on Ad Spend (ROAS) metric appears greyed out and can't be added to their current selection of dimensions. According to the platform’s reporting logic, what's the cause of this restriction and how is it addressed?

In Report Editor , a metric can be unavailable when the current dimensions are not compatible with that metric. Google’s reporting logic uses compatibility rules, so a greyed-out value such as ROAS indicates the current table setup cannot support that combination. The Show incompatible control is used to reveal or hide metrics, dimensions, and segments that do not fit the current selection. To add ROAS , the user must review compatibility in the selector and adjust the report to a compatible set of dimensions. Google Help