 The Difference Principle is also criticized as a primary distributive principle on the grounds that it mostly ignores claims that people deserve certain economic benefits in light of their actions. Advocates of desert-based principles argue that some may deserve a higher level of material goods because of their hard work or contributions even if their unequal rewards do not also function to improve the position of the least advantaged. Desert theorists as well as libertarians also argue that the explanation of how people come to be in more or less advantaged positions is morally relevant to their fairness, yet the Difference Principle ignores these explanations.