I sent out my resume online and a recruiter contacted me after a couple of days, requesting a pre-screen phone chat. He generally wanted to know more about my background and let me know about the process ahead. He, then, went ahead and scheduled my first phone screen with an engineer in ads department. The screen went OK, I guess but the interviewer seemed too insincere with the smalltalk and job related questions. I gave an answer to the question, he thought me that the answer is fine but it may not be complete and told me to email him a better one if I might find. Right after the interview, I rewrote another solution and emailed it to him. After about a week, the recruiter contacted me again to schedule a new screen. This time, I was slow and a bit erroneous to give the correct answer. What's interesting was that the recruiter was kind enough to phone me to tell me that they won't go ahead with an offer this time.