The entire purpose of the interview is for the manager to decide whether he likes you and if you're the best fit for the job. Many interview questions, including this one, center on the broader question of "What are your strengths?" Before the interview, list your strengths and compare them to the job. Identify the three or four best matches. Throughout the interview, including your response to a "work ethic" question, you should carry on the theme by emphasizing those strengths.