What causes some people to wish harm for others?

[MiracleSurvivor]

I find some people do because they have psychological problem, they hate themselves, or they have low self esteem.

but there are two Arabs that seem very happy when something bad happens to the other person.

 

[Umm Malik]

sister ... the first thing in this feeling besides the problems you mentioned
it's because that person didn't happy with his situation ... or he thinks like he have nothing while other people having more than him
and because they don't know that Allah gives people as testing and take from them as testing
but sister ... please don't think that all arabes are like those two people
they may one day be better than as
this is Maryam with you Arab and Muslim sister