As slavery evolved and it became permissible in society to treat slaves with less and less regard, more labor could be demanded from each individual, which meant more profit from the owners. In America, especially the United States, it is possible that slavery was responsible for the development of the American middle class, because it established a caste-system and gave birth to the concept of white privilege. Slavery was certainly pivotal in the boom years of America's early economy. Despite the fact that slavery had some advantages, the price for those advantages was staggering. As the transatlantic slave trade increased, the old reasons for enslavement largely fell away, and an increasing number of Africans were kidnapped into slavery solely for profit. Furthermore, once enslaved, these people's children were trapped into a life of slavery as well. Millions died as a direct result of the brutal conditions of slavery....

Slavery also established a caste system in Africa, America, and much of Europe. Finally, the slavery system made Africa economically dependent upon Europe and America; it continues to struggle with its dependent financial situation to this day.
As the above examples make clear, there were benefits and detriments to slavery. Without slavery, it is unlikely that America or Europe would be as prosperous as they are today. However, without slavery, it is equally unlikely that most of present-day Africa would be considered "third world" or that the de facto color-based caste systems that permeate much of Africa, American, and European culture would continue to exist.