After my final round, I waited patiently ... and then waited some more. I emailed my recruiter, my "buddy" and my interviewers. I really was interested in working there but I had to make a decision on other jobs. I told them that and they said someone will contact me. 6 weeks later, after I had already taken another job, a recruiter called me saying that I didn't get the job because I did not make their "bar" and a partner will call me with feedback. 3 years later and still no call.
I guess I should be happy that they did eventually contact me but it left a very bitter taste.
Fast forward to two months ago. I was in the position of finding a consulting company to help our hospital system with financial issues. 3 large hospitals. Multimillion dollar contract. McKinsey & Co.'s name came up a few times but my bad experience is what made me eventually recommend another company. One that I got rejected from after the first round but made me feel good. They gave me feedback and didn't make me feel like crap.
Most people claim that McKinsey has a great feedback system, but it failed in my experience and maybe that is what led to us choosing another consulting company.
It taught me a great lesson though. Regardless of who I interview now; resident, attending, or any other position, I personally call them to let them know our decision.