This simple delivery is becoming a pain as the T&C's associated to it are not 100%
However,if the item was damaged by the carrier in transit then ebay pay for the damage to the buyer and refund them,but you may still be responsible for the refund.
See below.
12. Liability for Loss or Damage and Compensation.
You remain responsible for any loss or damage to your item until it has been scanned into the carrier’s network. Once your item has been scanned into the carrier’s network and providing you used the Simple Delivery label and are compliant with these Terms and eBay’s Policies, as well as the relevant Carrier Terms, your item will be covered for loss or damage during transit up to the sold item value on the eBay.co.uk site. This means you will retain your sales proceeds in relation to the item sent using the Simple Delivery label. The item will be in transit from the point it has been scanned into the carrier’s network until it has been marked as delivered by the carrier.
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