This is all good stuff, I've started getting into the more serious interview phase of my own job hunt so all of this helps. I especially like your input @droxford .
Not when I'm both restating and explaining a hypothetical answer to a question that entails self-criticism during a competitive process.
Human Resources checking in. If your interviewer asks this bland question more or less verbatim, then you're ok with using one of the generic answers posted here. They're likely not digging too far into your answers anyway. But, trust me when I tell you that there are a million different ways to get the genuine answer to these questions. So when faced with specific behavioral based questions, be mindful of how you answer. And be honest. A good interviewer will reveal weaknesses with their line of questioning and if you're not honest you may attach yourself to weaknesses that may not be accurate. Or you'll make it obvious that your most glaring weakness is a lack of honesty and integrity. Also, a good interviewer/panel will make you feel extremely comfortable. They'll make jokes and they'll all laugh, one of them may even find a way to relate to you in some way. They'll get you to relax, sit back in your chair, and... Spill the beans. I've seen this happen to people without them knowing what hit them. I've also seen people clam up as if they have something to hide. I've put in a lot of time to become a good interviewer, and I'm pretty good at exposing the fakes. But many in the industry aren't. You may not even have to worry about any of this, especially if you're a straight shooter to begin with.
Guess what. I have flaws. What are they?. Oh, I don't know. I sing in the shower. Sometimes I spend too much time volunteering. Occasionally I'll hit somebody with my car. So sue me!
Answer the questions like this... Biggest strength: I am a clinically diagnosed sociopath capable of creating total chaos in the work place. Biggest weakness: I keep getting the women in my workplace pregnant.