What does the interviewer want to know when they ask you this question? Essentially, they're asking, "What problems did you have with your last manager, and what did they consider your weakness?"
Just like an interviewer asks you about any problems with your boss, the purpose of this question isn't to make you talk about what a horrible person you are. What they want to know is how you can honesty answer a question that could potentially make you look bad.
How to Talk About Weaknesses
Another way this question will be phrased will be "What are your weaknesses?" or "What do you feel your weaknesses are?" Both of these questions are designed to give the interviewer an idea of where you feel improvement is needed in your life.
You DON'T have to admit that you have weaknesses, but the truth is that everyone in the world has something they need to work on. Whether it's your team-working skills, your ability to get along with people that irritate you, or your punctuality, there is going to be some area of your life that can use improvement.
If you insist that you don't have any areas where you need to improve, the interviewer is going to think you are dishonest--which could ruin your chances of landing the job. You need to give an answer to this question that helps you to admit your shortcomings, but without making you look too bad.
So how can you answer this question?
- Think about the areas where your boss told you that you needed improvement. No doubt there was something about you that he or she wanted you to work on, so take some time to think about anything they could have said that indicated areas where you fell short.
- Phrase it to show positive change. For example, "My boss said that I needed to be more organized, so I implemented a system that helped me to prioritize my work." Even if you didn't make huge steps of change, at least show you took the advice from the boss and acted to improve yourself.
- Mention the fact that you and your former boss never had any issues. If you never had run-ins with your former boss, it's unlikely that he/she told you flat out, "You need to work on this." If you can't think of anything your boss specifically told you, mention that fact to get out of having to mention any weaknesses.
Of course, if they phrase the question differently, you may have to come up with answer. For example, "If I were to call your old boss, what areas do you think they would say you need to improve in?" This one is a much more hypothetical question, and you can't really dodge this one. This is where coming up with a positive-sounding answer is the smart way to go.
Above all, when answering this question, keep it short. You don't want to get into details with this question, but answer in a few succinct sentences. Try to spin it to make yourself look good, but try to get past this one as quickly as you can without seeming ashamed or embarrassed about your mistakes or weaknesses.