Phone Discussions, Personal discussions 3 rounds, Global Rounds from US, HR round

They called scheduled interviews on 9th Apr 2016 (Saturday) ; my scheduled time was 10.00 AM and they kept me waiting for 5 HR's; at last at 3.00 PM they called me into the cabin, and asked some basic questions just for 15 mins; and they asked me to leave. It's just complete waste of time. When they kept waiting the candidates for 5-6 hrs. not even given any communication & respect when dealing with the people