Plastic pollution compromises ocean health, with large amounts of plastics continuing to enter marine and coastal environments. Various mitigative engineering solutions arc being developed and implemented in response to this threat. While recognising the positive impacts of clean-ups, we highlight two perspectives given little attention to date, which are vital to evaluating the cost-benefit ratio of clean-ups: firstly, clean-up efficiency where density and accessibility of litter are key, and secondly, potential negative externalities that implementation of clean-up technologies may have. These principles, catch per unit effort and the impact on non-target species, are well known from fisheries management. We argue they should also be applied in evaluating marine litter removal schemes.