In a Shopping campaign, conversion tracking grants access to Search Funnel reports, which show how your customers complete a conversion.

Explanation: Once you’ve set up conversion tracking, you’ll have access to a handy set of reports about your conversions.

Attribution reports show you the paths customers take to complete a conversion, and attribute the conversion to different ads, clicks, and factors along the way.

Read more here: https://support.google.com/adwords/answer/1722023