There are too much problems in people's lives and people cant think clearly and they only think future because of they cant focus now and their brain is too bussy in this century more than before so we cant listen birds sound and we cant feeling clean weather and it is really bad and sometime i ask myself " i am alive or not!"
In my opinion, people become unhappy because they are not contented and satisfied of what they have in their life. Sometimes, some people are unhappy because they get so envious for the success of others.