Sathyaish - Sorry to hear about your experience. Microsoft has a very large recruiting organization, and often our subs do business differently than we do at corporate so I can't commit on the reasons behind your experience.
Since you mentioned our blog post on using third-party recruitment firms, I wanted to clarify that Zoe and I said that our specific team doesn't use third-party firms to short-list candidates. I am not familiar with how other teams operate.