Receiving a beating at an interview

It's happened to me twice so far in my career.  I've hung up the phone feeling beaten up after an interview.  I love and hate these types of interviews.  Both have been with "big boys" of my industry, Amazon and Google.  I pretty much knew going in I was going to be destroyed.  In both cases I was actually a little surprised because the questions were not overly complex or even necessarily very difficult.  The format was this. I would be asked a seemingly easy question, what is this or that?  How does such and such work?  After answering the questions the response is typically, "ok good, you said xyz happens.  How does xyz work?"  It feels like you just had a missile shot at you and the interviewer is essentially yelling, "Dive Dive Dive!"
Next comes the part that leaves me feeling defeated.  The barrage continues until we get to the part of "Why is this bad?" or "Should you be worried about that?"  or just a simple "What else?"  Because sometimes there are no more "what elses"  sometimes the answer is "Nope, it's not bad so no need to worry."  Typically I can spew out one, maybe two, more what elses before I raise the white flag of surrender and admit I'm done.
I have also found that the tone of the interview can totally be determined by your interviewer.  With Amazon I had a great first interview with a guy from Ireland.  The accent wasn't an issue and we really had a great conversation.  I did really well.  The second interview was with someone here in US and it was awful.  In some interviews the interviewer will prompt you if you are struggling and rephrase questions or describe them a little differently.  Not so for this guy.  He'd ask a question then silence.  I'd answer and he would retort, "ok."  Then proceed to the next question.  That one didn't go so well.  Not to mention I bombed a pretty easy coding question.  I'm not a developer by nature so reading code over the phone is not a comfortable thing for me.
My interview with Google I felt went ok.  Not great though, and probably not well enough to continue in the process.  I've not gotten intimate with linux internals or network switching in quite some time and we spent a good deal of time on those areas.
In my experiences with both Google and Amazon I do feel that I came out of the interview a more intelligent person.  I thought about things differently and in ways I haven't thought before in a long while.  These deep dives result in a stronger knowledge base in the end.  They also expose weaknesses and strengths to be better prepared for next time.  Yes, there will be a next time.  Maybe not with Google, maybe not with Amazon, but with someone, somewhere.
So if you've felt beaten by an interview, pull yourself up, identify where you think you failed and why you think you failed.  You'll be a better candidate due to the experience you gained.