No matter how hard you try, if someone is lying to you, he will eventually lie whenver he gets any chance. So even if we try to give second chance there is no guarantee that he will not betray us again.You are absolutely right @Pousinha, although it is difficult for a dishonest person to correct himself, there are cases! In my job site I saw the radical change of a dishonest person, when he realized that he was about to be fired from his job.