why families do honour killing

Summary: 
              Honour killing means the killing of a member of a family who is perceived to have brought dishonour to relative. Many cases have happened. For example, last year in India, a young couple were murdered in Haryan state because they planned to marry despite being from the same caste. Nidhi Barak, 20, was beaten to death and Dharmender Barak, 23, dismembered alive. The idea that a murder can be honourable is believed to come from tribal customs where an allegation against a woman can be enough to defile a family's reputation.
Opinion:
           I think that honour killing is very cruel and horrible as they have to take away a relative live or even more. What is worse is that many cases like this happened and there are so many victims that were attacked. There is no honour in killing. It certainly does not do any good to anyone.