Why does Golding create two contrasting characters in Lord of the Flies who struggle over the leadership of the island?

Golding creates two contrasting potential leaders in Lord of the Flies to highlight the key thematic elements of the novel. The novel presents savagery and chaos in competition with reason, logic, and adherence to formerly acceptable societal norms. Jack represents the human desire for turbulence and leadership exerted  by strength, while Ralph continues to try to lead through logic, reason, and the rules of the society they left behind.

In addition to creating the main themes of the novel, the two contrasting characters also provide a platform for the plot of the novel to progress. The conflict between Ralph and Jack is a microcosm of the conflicts overtaking the whole island and all of the boys. Jack's takeover of leadership ignites the descent into madness that the boys embark on, while Ralph's presence constantly sheds light on the failures of the new society.

The conflict for leadership in Lord of the Flies is one of the central components of Golding's book. It creates the themes that permeate the entire story, and sets up the main characters that drive the plot development of the book. The conflict between leaders is one of the most important parts of Lord of the Flies.