Question - What was the biggest mistake of your life?
Answer -
At the time of answering this question, you should choose a story containing not too many mistakes. It should be real.
Talk about the mistake, but it is also important to convince the interviewer that you never make the same mistake again.
For example:
I think the worst mistake I ever made at work was in my first ever job - five years ago now. A more senior member of the team seemed to take an instant dislike to me from the start, and one day she was particularly unpleasant to me in front of several colleagues.
Later on, I was talking to one of those colleagues who was, I thought, attempting to console me. Angry and hurt, I foolishly vented my feelings and told her what I thought of the lady in question. I was naturally shocked to find out that she went on to tell everyone what I had said and this certainly didn't help my relationship with the team member who was causing me problems.
Rather than let the situation carry on, I chose to have a quiet word with this lady to find out what her problem was with me and to see if we could put it behind us. It turned out it was nothing personal; she just resented the fact that a friend of hers had also been interviewed for my position and had been turned down. Once we had got matters out into the air, her behavior changed, and we got on quite well after that. However, I certainly learned a lot from experience. I learned that careful communication is vital in managing interpersonal relationships and that if I have a problem with someone, it's always best to talk it over with them rather than with someone else.