The default attribution model in most analytics platforms is last-click. It's also almost certainly wrong for

The default attribution model in most analytics platforms is last-click. It's also almost certainly wrong for your affiliate business.

Last-click attribution gives 100% of conversion credit to the final session before purchase. For a user who discovered your site via organic search, returned twice through direct, and converted after clicking a retargeted ad — the retargeted ad gets all the credit. The content that built trust across three sessions gets none.

This creates systematic misallocation of marketing budget. Teams optimize for the last touchpoint and abandon high-quality top-of-funnel channels that don't show direct conversion credit.

For affiliate marketers, this matters most when you're running multiple traffic sources. If you're spending on both content and paid, last-click consistently undervalues content's role in the conversion path.

The fix isn't to pick a "better" model and call it done — it's to run multiple models in parallel and look for the gaps. Where does last-click attribution heavily favor a channel that data-driven attribution rates lower? That gap tells you where your reporting is flattering underperformers.