Marketers are used to having to prove digital advertising’s worth, but findings from Econsultancy and Google Analytics suggest the majority of marketers worldwide failed to use attribution models that properly depict the influence of each ad format and marketing channel on the consumer’s purchase path.
Instead, they justified and planned digital marketing investment using last-click attribution models.
The last-click attribution model was the most common method used by marketers and agencies worldwide. Under this model, the last click receives full credit for any revenue generated.
Some last-click models factor in both marketing and paid advertising influences, but under the paid search last-click model, only paid ad formats such as search and display are credited. Social media or organic search clicks do not receive credit, which makes it difficult for marketers to justify investment and spend on non-advertising marketing tactics or to know from where else they are driving purchases
Last-Click Attribution Models Give Marketers Incomplete Picture - eMarketer