To be honest, I agree with the parent that the question is wrong. No company wants employees that are bad at interviewing. No company wants employees that are bad at anything, in fact.
Maybe it helps to contact the company that rejected you and ask them why they rejected you. This would allow you to narrow down your weaknesses and improve these skills. I've never tried this myself, so I'm not sure how common such a request is, but it seems like a sensible thing to do.
Doesn't cost anything to try though. We actually do attempt to give straightforward answers to candidates that are not a good fit, although we are a smaller company that doesn't have the concerns that a large corporation has
Or any answers. At least for the US, I've read before here on HN that it may be due to the company's fear of being litigated against for some sort of discrimination.
Maybe it helps to contact the company that rejected you and ask them why they rejected you. This would allow you to narrow down your weaknesses and improve these skills. I've never tried this myself, so I'm not sure how common such a request is, but it seems like a sensible thing to do.