This question always has you scrambling for an answer, it touches a raw spot and can be humiliating, but you can turn it around by facing and using the facts of the matter.
The facts are that you are a hardworking, competent professional who had always been led to believe that
was enough. You’d never had a problem finding work before and no one had ever told you there were specific job search skills you needed to develop, not at home, school or college or anywhere.
Then you got sideswiped by the biggest recession in eighty years and on top of this, the sudden move Internet-based recruitment (while you were working and not paying attention to such things) had changed all the rules of job search anyway.
You might try something along the lines of, “If you look at my work history you’ll see it has been steady for __ years. Then I lost my job. The big problem for me was my complete lack of understanding about how to find a job in the worst recession in eighty years, at a time when recruitment had moved entirely online and changed all the rules of job search.”
“I’d never had a problem finding a job before, but because of the changes in how you find a job today, when I did apply for jobs, most of the time my resume got stuck in a database and was never even seen by recruiters. I didn’t understand that my resume had to be written differently. The big reason I’ve been out of work is that my resume didn’t work in this new environment and I just haven’t been getting interviews.”
Then move the conversation forward to what’s most important to the interviewer: what you can do and how long it will take you to be productive. You might finish with a question of your own, asking about the most difficult and/or urgent responsibilities of the job and why people fail in this job, “but put me to work and I’ll get right back to doing what I do best: identifying, preventing and solving problems. What are some of the recurring problems your people have to deal with in this job?” The interviewer’s answer should give you ammunition to talk about how well suited you will be for the position.