Social identity theory proposes that people have emotional reactions to the failure or success of their group because their self-esteem gets tied into the group's performance. When your group does well,you bask in reflected glory,and your own self-esteem rises. When your group does poorly, you might feel bad about yourself, or you might even reject that part of your identity,like"fair weather fans."Social identities also help people reduce uncertainty about who they are and what should do.