The ability to put an order into QC Failed status based on a failed carrier QC rules. Rules like these prevent the order being held up at the time of packing meaning that we don't need to fix order data at the packing bench.
This could be postcode verification or rules based on geography that are specific to carrier service.
This is a huge barrier for us as well but my thoughts are as follows.
New UK housing developments - can take ages for new postcodes to be updated across all couriers
What are the rules? Not all houses have a house number so would 'The Brambles' (address 1), Holly Lane (address 2) fail as there is no number? On the flip side, address one of 'Sycamore Street' would pass if you weren't quantifying house number but could be 100 houses on the street
What database do you subscribe to? Various ones in the UK but LOADS for the rest of the world! Also, would the subscribed database be the same as the couriers?
Do you highlight the various pitfalls to customers and they then decide if they implement postcode lookup / service determination at point of order so overcome issue but again, which database(s) do they reference?
Very difficult one in my mind.