What was the main goal of the coastal African kingdoms that were part of the slavetrade?

The main goal of the coastal African kingdoms involved in the slave trade was to maximize their economic gains through the exchange of enslaved people for European goods, such as firearms, textiles, and alcohol. By facilitating the capture and sale of enslaved individuals, these kingdoms aimed to enhance their political power and wealth, as the trade became a significant part of their economies. Additionally, engaging in the slave trade allowed them to strengthen alliances with European traders while competing with rival kingdoms for control over trade routes and resources.