What were the consequences of the slave trade on the West African economy?

The slave trade had a variety of effects on the economy of West Africa. Starting in the early sixteenth century, between 12 million to 15 million West Africans were sold into bondage over the next four hundred years. The differences in the economic effects varied mostly by what role different groups of West Africans played in the process of human trafficking.
The vast majority of West African slaves were sold to Europeans by other Africans. Many coastal tribes grew exceedingly wealthy through the slave trade. Most slaves were captured by these tribes during wars. Some wars were fought exclusively for the purpose of acquiring prisoners to sell in the slave ports. As coastal tribes grew wealthier from the sale of Africans from the interior, they were able to finance even larger armies and slave-capturing forces.
African rulers and merchants in these areas found it necessary to safeguard their ability to capture and sell Africans from the interior. They often did not allow Europeans to venture beyond the port towns to capture their own slaves. In fact, this was convenient for the Europeans as well, who found it more profitable to supply other Africans with the weapons and means to capture potential slaves than to do it themselves.
The slave trade introduced many European wares to West Africa. As West African rulers grew wealthier through the direct trade of slaves or through taxing slave merchants who passed through their kingdoms, they became increasingly fond of European imports to Africa, such as cloth, jewelry, and weapons.
While coastal areas of West Africa prospered greatly through the slave trade, it devastated the economy of the interior. Although all people were targets, slave catchers tended to focus on kidnapping young men who could fetch a higher price in the slave ports. This practice, especially after a large raid, could wipe out the entire work force of a tribe at once. This led many communities to starve or disintegrate entirely as individuals sought shelter in the wilderness or sought to join other communities. As a result, the slave trade led to a huge decrease of the local population.
Overall, the slave trade had a negative impact on the economy of West Africa. Individual kingdoms may have benefitted financially from the trade, but overall, it was a huge loss for the region. Since human trafficking involved disruptive conflicts, the destuction of communities, and the removal of a large amount of the workforce, regional trade routes and partnerships were very unstable. A successful economy needs peace and stability to thrive. The chaos brought about by the slave trade greatly held back any economic enterprise not directly related to human trafficking. The impacts of the slave trade were so far-reaching that many economic historians believe that the region has yet to recover from it.
http://www-personal.umich.edu/~baileymj/Whatley_Gillezeau.pdf

https://www.aehnetwork.org/blog/the-trans-atlantic-slave-trade-and-local-political-fragmentation-in-africa/