What it is
If users can make purchases on your site, it’s important to know when this happens and who is making the transaction. Correct cross-domain tracking can be important here, but we also very strongly recommend ecommerce tracking. This means not only is the transaction recorded but also the amount and what was bought.
There is also an extended version of ecommerce tracking available, called enhanced ecommerce. Here, product views (and a bunch of other useful information) are also recorded. So you can see which products got seen but not bought, and which products need to be more visible.
Why it matters
Let’s say your site sells widgets that range in price from $10 to $100. You have a paid advertising campaign with an average cost per click of $0.50 and an average conversion rate to finished purchase of 2%. That means a sale costs $25 to generate which is fine if you make $100 on the sale but not if you make $10.
The campaigns that are most profitable might not be the ones with the highest conversion rate. Because revenue per sale is a factor too – and one that can make all the difference between costing your business money and making it.
What to do
If you are using a common ecommerce CMS like Magento or Shopify, getting enhanced ecommerce data can be as easy as changing a setting.