third suspect nabbed!

A third suspect was nabbed by the West Bengal cops today in the Hyderabad bomb case.the suspects were tracked by the SIM card used to set off the bombs,out of which 2/3 of them did not explode.first of all i fail to understand the logic behind such attacks.why is it that there are some of us who just because they feel miserable think that it is okay to kill innocent lives.if they are so miserable then why do they not end thier own lives thereby doing themselves as well as us a huge favor?
i hope that the courts do award these suspects harsh punishment!