The interviewer wants to hear what you like least about your job to see if what you dislike will interfere with your performance if hired. For example, if you state that you dislike working with people, you might not get chosen as a candidate since your job entails working with other individuals. A better answer is to say that you dislike it when the weather prevents you from working, you do not like it when other operators do not take care of their equipment, or you do not like the instability of your job due to the climate or economy. Describe what you like least about your career and explain how you overcome it and perform your job successfully.