According to the passage, the change from informal to formal empires was:

The drive to acquire political control of tropical regions was almost universal among the major European nations in the nineteenth century. Where did the empires spring from, a greed for territory, a lust for power, accidental circumstances, or an economic motive? J.A. Hobson suggested that empires rose to protect European investments abroad at a time when the need to export capital was acute because of falling rates of return on capital at home. Competition for colonies, Hobson believed, lay behind the conflicts that dragged these powers into war against one another. The more common motives cited were markets for goods and openings for emigration, not the export of capital, and investment was seen as a means rather than the end. J. Gallagher and R. Robinson held that Britain had already built an informal empire secured by commercial, cultural and diplomatic links, and the change from informal to formal empire was driven by global and local political rivalries rather than by economic motives.