I was called for a hiring drive on a Saturday to their office. Initially they had a written round where they asked me to design a url shortener system. After giving me only 10 minutes for that design problem, the HR called me for a F2F round with one of their Technical Leads. Interview lasted only for 30 minutes including the discussion on URL shortener design. It looked like the interviewer was not interested in the process. Even though I was able to answer almost all of his questions and I was able to design the url shortener system very efficiently in those 10 minutes as I had recently studied on the same design few days back, I got rejected.
After 2-3 days, I sent an email to the interviewer asking to share the detailed feedback as I was surprised by the rejection and wanted to know the reason. He sent a response "we have moved forward with the other candidates". This clearly showed that he was not able to justify the rejection and he simply wanted to escape the situation. It was a sheer waste of time.