When I interviewed at Google it was 2006 and they had a reputation for rejecting nearly everyone. I was still a student! So I rocked up to the interviews calm as calm could be because I didn't believe for even a second that I'd actually get the job and really, the whole thing seemed like an entertaining and potentially interesting mistake.
I've never applied to Google and I never will, because it would be nearly impossible for me to perform in one of their interviews.