The only thing I can think of is the business sends open ended...

The only thing I can think of is the business sends open ended invoices with shipment therefore do not get paid if the product is not sold, although with the recent announcement they stated for the RBCGO launch :-
‘The Group has incurred higher product manufacturing and operating costs for the quarter, primarily as a result of the manufacture of the finished products for RBCGO. Revenue of NZ$470,000 will be recognised in the financial accounts (and future cash flows) on the sale of the product.’