Retrieval lines are mainly used – as the name implies – to retrieve the pilot ladder after use. It has often been argued that they can be trip hazards for pilots, getting on- or off the speed tender. The rule of the thumb for the correct use of the retrieval line is: above the spreader, leading forward. And even then it is still risky.
The below clip ships a pilot disembarking a ship getting entangled in the ship’s retrieval line.