Siemens Senior Software Developer interview questions

They had taken six technical rounds of interview asking about Java and Hadoop. Two client rounds one Video Conference and one face to face. I had a very poor experience, even after 6 rounds of interview and saying that all the rounds feedback are positive. And then after 3 days i got a call from consultant that you have been rejected and they didn't gave any reason. Also i sent a mail to Head HR of Siemens asking the reason of rejection but no update.

overall very good 4 round in total, 2 technical, 1 managerial followed by HR, interview was average , process took 2 weeks to get the offer.overall very good 4 round in total, 2 technical, 1 managerial followed by HR, interview was average , process took 2 weeks to get the offer.overall very good 4 round in total, 2 technical, 1 managerial followed by HR, interview was average , process took 2 weeks to get the offer