Why is there a pending authorisation shown in my PayPal activity for my PayPal Pay in 3 transaction?

When making a purchase with PayPal Pay in 3, we will place a pre-authorisation hold on your chosen card for an amount equal to the initial payment or one third of your total purchase amount.  This will show as a pending authorisation in your PayPal account activity and also in the bank account of the card linked to your PayPal account.  Once you complete your purchase with PayPal Pay in 3 and the merchant ships your goods, the pending authorisation will be removed and the initial payment will be withdrawn from your card.  If you do not complete your PayPal Pay in 3 transaction, the pending authorisation will be automatically voided by PayPal within 72 hours of the pre-authorisation hold.