There were multiple rounds including an assignment. The persons who took the last round started discussing without being aware about the topic of the assignment. The biggest positivity of design is everyone wants to participate and the unfortunate part of it is everyone wants to participate as expert, not a user. Now, like any other disciplines, design needs continuous learning and experience in background. Now, if someone from absolutely different part will try to give lesson on it, try to criticise the design of a very popular product where the design gurus spent their ages, it is nothing but pure arrogance. Well, I would say, the company should take some professional help to learn how to conduct interviews, specially how to speak with experienced candidates from big giant product companies.