If a channel appears anywhere—except as the final interaction—on a conversion path, it is considered an assist for that conversion. The higher these numbers, the more important the assist role of the channel. ... The final click or direct traffic before a conversion gets last interaction credit for that conversion.
In Google Analytics, it’s important to understand the difference between ecommerce and non-ecommerce credit. Ecommerce credit is when someone comes to your website, views a product, and then makes a purchase. Non-ecommerce credit is when someone views a product, but doesn’t make a purchase.