Checkout abandonment and cart abandonment are not the same.
Shipping cost is the number one reason why users abandon checkout. On step-1 of checkout, user enters their details (name and email) to start checkout and view shipping costs. If they didn't place order after initiating checkout, we will treat them as users who've abandoned checkout.
If identified user add item to cart but didn't place order, we will treat them as users who've abandoned cart.