Attribution models, briefly

Somebody finds you through a search, reads a comparison on another site a week later, then arrives directly and buys. Which of those gets the credit?

Last click gives it all to the direct visit, which is the least informative answer. First click gives it to the search, which ignores the week in between. Everything else splits it up according to a rule somebody chose.

None of them is true, because the question does not have a true answer. What matters is picking one, writing down which one you picked, and not changing it in the middle of a comparison.

We use last non-direct click, mostly because it stops “direct” absorbing credit for everything else. It is not more correct than the alternatives. It is just less flattering to the channel that deserves the least.