Depends on the context. Usually, i don’t care too much. Like if the author wants to show themselves at the end while answering an FAQ or whatever, it doesn’t bother me. However, I definitely don’t like when authors show up in the beginning of the story announcing that it’s their first story or apologizing for the story being bad or saying “it will get better after this!!!” Blah blah. It’s really off putting since it doesn’t make me believe the author has tried to put their best foot forward. It’s not like everything has to be perfect all the time. But announcing your story as “this sucks And I’m not happy with how it turned out” really isn’t going to endear the readers to the story. The same applies if this message is left for the end.
But if authors appear at the end of the story for whatever explanations or announcements they have, I don’t really mind. I know a lot of people really don’t like it, though.