Slave trade was complicated and aimple at the same time.
“Taking the Dahomey region as an example (drawing from Lee, Waging War, 265-72), you can see the clear impact of that strategic dilemma as the slave trade explodes, from perhaps three thousand enslaved persons traded out of the region per year in 1670 to twenty-thousand in 1688. As flintlocks flooded into the region, their price relative to enslaved persons plummeted, from two guns per-enslaved-person in 1682 to 24-32 guns per-enslaved-person in 1718. And that price movement, which is increasingly less favorable to European slave-traders as time goes on, speaks to the degree to which West African states were active participants in what was happening. “