on 18-01-2016 03:23 PM
I presume you are not a seller or else you would know that for a good proportion of ebay sellers using couriers is just not possible due to the volume of items they are sending. Unless you are posting off dozens of parcels a week you cannot get a cheap enough rate to beat Aus Posts costs. Also couriers will not deliver to PO boxes so that makes it a problem for your average small scale seller too.
You also have to pay quite a lot for even basic tracking and insurance with couriers and while some of their deliveries may be quicker tha AP a lot are not, certainly not quick enough to make buyers want to pay a lot more for their item.
Ebay ratings are meant to be based on when the seller posts the item, not on how long anyone takes to deliver it. While I think the majority of people realise this there will always be some who are not that bright and will rate based on how long the delivery takes but fortunately in my case they don't buy from me as my postage time DSR remains at 5 as it has done for years.