The problem with the society we live in today is that people tend to easily assume the worst in others. When a person commits a wrongdoing, we tend to dismiss the fact that he or she are human. We tend to dismiss the fact that humans are bound to make mistakes. We assume the worst in others before we give them the benefit of the doubt. How can we expect someone to change for the better when we can't even accept the idea that 'they can'? I believe that in order to influence someone for the good, you must first believe that 'one does have the potential to be better'. I also believe, that you must give them the chance to show that they can. Instead of being so fixated on the idea that a person can never change, consider the fact that they can, so when they actually do, you can finally see it.
:قال تعالى
{...يَا أَيُّهَا الَّذِينَ آمَنُوا اجْتَنِبُوا كَثِيرًا مِنَ الظَّنِّ إِنَّ بَعْضَ الظَّنِّ إِثْمٌ}
سورة الحجرات٠