There are several reasons why an author might want to write in a first-person point of view. It is very likely that the author wants to tell a story that he participated in. In this case, writing in the first person would most likely allow the author to explain his personal point of view. He might also be able to provide details that only he would know about. Finally, an author might write in a first-person point of view in order to be able to discuss his personal feelings and opinions.