Abandonment rate is a term that is used somewhat loosely but most commonly refers to the desertion of a shopping cart on an eCommerce website. Abandonment refers to the situation when an online buyer loads up his shopping cart with items he wishes to purchase, but then changes his mind at the last moment and simply exits the website leaving the cart full of un-purchased items. The term could also refer to a singular opt-in action, that is, the number of people who exit a website before the completion of some pre-defined target. For example, a website with the abandonment rate of 80% simply means that 80% of its visitors leave the website before completing the checkout process.