UBS Senior Developer interview questions

My interview was scheduled via a staffing company. I reached the UBS office at around 10:15 am as scheduled. I had already appeared for their online test and had cleared that still they asked me to go for written test again. I completed the written test and the result was positive. At around 11:30 they told me that I have cleared the written test and my next round of F2F interview will happen shortly. From 11:30 a.m I waited for my F2F interview but I was not called. Even the candidates that came after me were done with their interviews. Finally they called me for F2F interview at around 5:30 p.m. in the evening after 6 long hours. I was tired of waiting till that time. It was pathetic experience. The was not proper coordination. There were not even enough people in the interview panel.