What is tight packing in slavery and why did this practice emerge?

Two philosophies dominated the loading of a slave ship. "Loose packing" provided for fewer slaves per ship in the hopes that a greater percentage of the cargo would arrive alive. "Tight packing" captains believed that more slaves, despite higher casualties, would yield a greater profit at the trading block.

"Tight packing" captains believed that more slaves, despite higher casualties, would yield a greater profit at the trading block.

necessary and proper clause. the congress shall have power to all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states, or in any department or officer thereof.