Why was the route from Africa to the West Indies called the Middle?

PassageThe middle passage was the second of the three routes in the triangular trade. or
The middle passage was the first of the three routes in the triangular trade. or
The middle passage was the third of the three routes in the triangular trade.

The middle passage was the second of the three routes in the triangular trade because it was the middle leg of the journey, transporting enslaved Africans from Africa to the West Indies or the Americas.