Whom is responsible to reimuburse a buyer for a 3 day delivery guarantee banner on my listing???

[silverknot]

I have some very inexpensive items at cost and ship these ECONOMY because the tracking fee at

times is double the cost of the item. YET, on occasion EBAY POSTS THEIR 3 DAY GUARANTEE DELIVERY

BANNER ON SOME OF MY ITEMS....even though I have the listing set up with ECONOMY Shipping (1 to 

 10 day delivery) and ALSO state very plainly WITHIN that item descriptive that it is a 4 to 10 day shipping

for this item.

 So when the  buyer complains that they had not received their item within 3 days and Ebay guaranteed that

it would be delivered, whom is responsible to refund this buyer because they open up a request on that

guaranteed delivery on day 4 or 5 when it was clearly stated that the item is a 4 to 10 day delivery??

[pjcdn2005]

eBay guarantees the delivery by a certain date if your listing qualifies for 'fast and free'...so anytime shipping is free and they think it can be delivered in 4 business days or less.  There is more information here..

https://community.ebay.com/t5/Announcements/eBay-Now-Guarantees-Fast-N-Free-Shipments/ba-p/29127299?...

It doesn't make sense to me why they would do that for an economy shipping listing, especially when you're using a generic term and they don't even know which service you're using.