Why does Authorize.net show order line item quantities incorrectly?

Question: Why does Authorize.net show order line item quantities incorrectly?
 
Answer: Due to limitations of Authorize.net's API, we are unable to send the line item level quantities. The integration currently doesn't allow for sending the unit price of the item, only the line item total.
If we sent the real quantity per line item, Authorize.net would calculate the line "item total" x "line item quantity", causing issues during payment.