why does the narrator go to visit usher

The narrator goes to visit Usher because Usher, his childhood friend, sends him a letter describing his mental and physical illnesses and begging for his company and support. The narrator visits to provide companionship and help Usher through his mysterious illness and emotional distress. Usher's letter expresses his desperation and need for a friend, which persuades the narrator to travel to the Usher estate to offer comfort during a difficult time.