Goldman Sachs Risk Analyst interview questions

I did not have a good experience with the in person interview. I show up at GS and they keep me waiting at the door for half an hour and then they tell me my interview is rescheduled! I go back to the hotel and after one hour they call me and ask how come I'm not there! I really expected much more from GS. On the other hand, the people seemed very smart and asked very interesting and challenging questions.