[lukes]

I was once asked "What's the worst thing about you?". Fortunately I had prepared for it and said something about not being a confident presenter and then outlining how I was fixing that.

The only thing the interviewer learned was that I knew how to answer that question. However I learned that the interviewer was not someone I wanted to work for.

The downsides to asking that question far outweigh the benefits. An interviewer should be trying to give a good impression of themselves as well as finding out about the candidate and this question does the opposite.