Why did Jim fear the man on the island before they met?

Jim feared the man on the island before they met because of the ominous reputation surrounding the figure and the stories he had heard about dangerous pirates and criminals. The isolation of the island heightened his anxiety, making him imagine the worst about the stranger's intentions. Additionally, the unknown nature of the man created a sense of dread, leaving Jim to grApple with his own imagination and the potential threat posed by the encounter.