This interview question is seductive. We like talking about ourselves. We'd love to talk about that really cool job, how much fun we had doing it, and how great the team was to work with during that time. How that job set us up for our latest promotion.
But job interviews aren't about fun and games. Nor are interviews about what you wanted. The hiring manager doesn't really want to know about what our value was that we received from a job. The hiring manager wants to know how a job helped you to help the hiring manager achieve goals. The hiring manager wants to know if your work helped the organization.
Remember, you are selling your skills as a product and this isn't about you (sorry). It's about your customer: the hiring manager.
Here are the two key areas to hit when answering this question:
1. How you increased your job skills and/or capacity to handle work
Job skills are foundational in your ability to perform on the job. Without the job skills, you can't do the work. Showing how another job (or your current one) helped you increase your job skills -- add to them, enhance them, move them from novice to professional -- shows the hiring manager that you are interested in learning and want to enhance your ability to do the work.
Even better is if you can show those enhanced job skills were used in later work and produced great results.
2. How your work helped the organization
A powerful way to answer an interview question as it relates to showing your results is to start with, "I helped the company to..." and put in your results. It's the right relationship too: the company needs help and you, personally, helped the company (or department).
Hiring managers, after all, care about you -- but not that much. What they care about is if hiring you will help them meet their business results. Without the business results from your work, hiring you will be a failure.
Answer the question, then, on what results you achieved because you enhanced your job skills and that helped you make results for the company.
Could you answer what position has given you the greatest value in terms of your personal growth in job skills and how that produced results for the company?