Some very good writers use the first person in their stories. Some advantages and some cautions:
First person is good for character oriented works. We readers can look into a character’s mind. First person lets us live for a while in the mind of a strange or twisted character
It’s easy for the reader to accept what’s said by ‘I’ character.
The reader gets inside the protagonist.
First person has to be present at key scenes. At these scenes the protagonist only knows what he or she sees. The first person cannot say what is going on in another person’s head.
The narrator must be modest, even if her accomplishments are real. “I’m the best surgeon in the country.”
Sometimes it’s hard to keep the reader’s interest for 400 pages of “I.”
The description of the protagonist is limited. “I looked like this.”
Sometimes the first person is too close to the event to tell the story. e.g. a mother telling of the auto accident that killed her child.
First person narration must reveal the narrator’s character or it isn’t worth doing.
First person must have a reason for telling the story. Tale telling must be part of his character. The strong, silent type would make a poor first person narrator.