Uncovering what is and isn't working is the bedrock of an effective campaign, but as customers now consume content from multiple sources, accurate measurement is becoming increasingly difficult to achieve.
The last-click has been the unchallenged method for measuring how customers enter the sales funnel for a long time. However, last click models don't provide a comprehensive picture because the path to conversion is never linear, it's multi-channel and multi-device.
Consumers navigate many touch points, both online and offline and it is impossible to trace just one definitive trigger point for a sale, which in effect, is what last click does. This complex reality calls for a more sophisticated measurement solution.
Improving attribution is an industry work in progress and there are limitations, primarily because every advertiser is different and has different objectives which cannot be reduced into a "one-size fits all" attribution model.
This means a consistent standard for the actual methodology of attribution is highly unlikely.