I'm not sure exactly why, but this story always has stayed with me quite vividly in my memory. The pictures are nicely drawn (presumably by the author, since no separate illustrator is listed), and the story is thought out well. "All by Myself" is a very memorable, short tale.
I remember reading this book as a kid. It was really very helpful in those last steps during potty training. It was like if she could do it then so can i.