Deloitte Software Engineer interview questions

It is like the most common form of an interview we can see that there is a written exam, group discussion and a Technical round followed by the hiring manager round and finally the issue of the offer.

1st round was a written test which had 10 questions on basic concepts of iOS. 2nd round was technical round where in they asked questions on the same test but digged deeper into those concepts (design patterns, auto layout) . Third round was again technical round but I didnt get through. I dont know what went wrong because I answered most of the questions that were asked.