Drawback has been around in one form or another since 1611.
It was brought in to provide relief from duty for traders who
imported excisable goods for sale in the UK, paid the duty and then
on receipt of export orders found that they could only fulfil them
by using duty paid stock.
At its most basic, drawback could be described as a method
for repaying excise duty on goods that have not been and will not
be consumed in the UK.