I don't know. I don't think it's possible to answer "why aren't you a good fit?" without knowing a great deal more about the company culture than I'd know early in the application process.

The answers that the author liked aren't answering the "good fit" question at all, they're answering the "what are your weaknesses?" question. That's an entirely different thing.

All of which probably just means I'd be a poor fit at that company, because it looks to me like they're looking for an answer to a question that wasn't actually asked.