We've all heard the advice to be prepared for any interview question that comes your way—but let's be honest, we can't think through every question that could be asked. That said, we should at least give some thought to the questions that are likely to come our way—particularly those pesky "take you by surprise questions" that have the potential to catch you off guard. Answer it the right way and you can practically feel the interviewer's satisfaction with your response—but screw it up and you might as well shut your folio right then, thank the interviewers for their time, and walk yourself out the door. Here are some examples of those questions and the thought process behind them.
Tell me about moving on from [previous position]?
The interviewer is looking to see whether or not you left under favorable or unfavorable circumstances. Did you outgrow the position, and the company had nothing better to offer? Was your work shipped overseas? These would be acceptable responses. On the other hand, being caught off-guard about leaving because of something unfavorable (terminated for non-performance, couldn't get along with your boss, etc.) and stumbling to come up with an acceptable explanation will surely set off alarm bells. Be prepared to account for why you moved on from each position listed on your resume, and consider how your reasoning will be perceived from the hiring manager's perspective.
What could you have done to improve your performance at [previous position]?
The interviewer is simply checking to see if you are a process improvement-minded individual. If you are, it will be obvious that you have given this some thought and will be able to offer up something such as, "In retrospect, had I taken a bit of time to brush up on my Perl scripting, I would have been able to perform certain tasks much more efficiently." Stumble on this answer, and you risk being perceived as someone who doesn't particularly have improvement on their mind.
What would you consider one of your weaknesses to be?
This remains an ever-popular interview question, but again, if you are unprepared to answer it, the first thing that comes to mind could be the thing that kills the interview. No interviewer is expecting you to spill your guts or reveal your darkest secrets. Instead, they are looking to see if you've given this some thought—and if so, if you've been able to frame it with a positive outcome. An appropriate response would be, "I'm not much of a socializer at work, but I've been working on that so I don't come across as unfriendly." This shows that a candidate has thought about their weaknesses as well as potential solutions, and it puts the candidate in a much better light than a response such as, "I spend too much time at work checking on my Amazon storefront."
With a few minutes of forethought and mental rehearsal, you'll be able to put your best foot forward and maximize your chance of being the candidate of choice.