Why did Madison believe that a pure democracy was not suitable as a model for a government of the United States?

Explanation:

Because he thinks the republic, The effect of the first difference is, on the one hand, to refine and enlarge the public views, by passing them through the medium of a chosen body of citizens, whose wisdom may best discern the true interest of their country, and whose patriotism and love of justice will be least likely to sacrifice it to temporary or partial considerations. Under such a regulation, it may well happen that the public voice, pronounced by the representatives of the people, will be more consonant to the public good than if pronounced by the people themselves

true

explanation:

it allows shippers to carry commercial goods, which allows them to save time and money.