The cottagers reject the creature because he

is different in appearance and scares them with his size and unnatural features. They also reject him because he does not fit into their society and is an outsider who does not belong. Despite the creature's attempts to be kind and helpful, the cottagers are unable to see past his frightening appearance and judge him based on his looks rather than his actions. This rejection ultimately leads to the creature seeking revenge and becoming a tragic figure in the novel Frankenstein.