Revenue data is religiously collected by financial departments
Revenue data is attributable in most organisations (although often only at a high level)
Revenues can be uneconomical (ie costs are more than revenue), and can be 'gamed' (for example by channel stuffing).
Profit is a true measure of the business value of all marketing activities.
To measure profit, we need to measure cost at the unit, activity and campaign level.
Cost attribution is generally harder than revenue attribution.
Definitions provided by Singapore's leading digital agency, Qais Consulting.