I think you left the interviewers some bad impressions about your technical skills. Blame the interviewers throw easy questions at you and think that it's all they get is blatantly wrong. Most Microsoft's devs are better than that! Based on my experience, the fact that you did not get harder questions show that they thought you did not sail through the easy ones as they expected. And believe me, knowing the answer is…
I'm absolutely positive that Microsoft Devs and Testers are top notch. That's why I wanted to work there and why I was sad about the result of the interview.
It was not me that didn't get harder questions. The other 3 that were interviewing at the same time said exactly the same thing (they gave the same problems to everyone). In each interview, with the exception of the second one that I solved two coding problems, I was asked a lot of behavioral questions before like 10minutes of the end, where I have to code.