When the liquidator of a company comes knocking on a creditor’s door, it is to echoes of "Queue jumper!" reverberating in the background. 

Essentially, one of a liquidator's first tasks when appointed is to identify whether any creditors have been given 'preferential  treatment' - that is, whether they have been paid some or all of their debt just prior to the company's liquidation and at the expense of other creditors.