Why did Vasco da Gama form an alliance with Cochin against Calicut?

Vasco da Gama formed an alliance with the ruler of Cochin primarily because the ruler was an enemy of the Zamorin of Calicut.1

During his second voyage in 1502, da Gama sought to undermine the trade of Calicut and punish the Zamorin for the favor he had shown to Muslim merchants, who were established competitors to Portuguese interests. By aligning with the Zamorin's local rivals—first in Cannanore and subsequently in Cochin—da Gama strategically positioned the Portuguese to challenge Calicut's dominance in the regional spice trade. This alliance was part of a broader Portuguese objective to secure control over maritime trade routes in the Indian Ocean and weaken the economic influence of their rivals.123