The interviewer wants to see what motivates you as a leader. You'll want the way you answer this question to reflect those instances where you felt a sense of accomplishment and personal and professional growth, or where you exhibited big-picture thinking and were instrumental in the success of the group and the advancement of goals. This can pertain to you as an individual or to leading the charge of the team. This approach will suggest you aren't the type of leader who equates to success with everything going according to plan or where everything feels easy. You want to equate success to accomplishment. As Margaret Thatcher once said, "Look at a day when you are supremely satisfied at the end. It's not a day when you lounge around doing nothing; it's a day you've had everything to do and you've done it."