We are Homo Sapiens that means that we can think, analyze, control ourselves and then act as with planning. That has been the main reason behind our progress.
We are part of a civil order and therefore we abide by the rules framed by our society, religion, culture, nation and the international community.
The combined actions churn our society and in the process some of us either by hard work, design, strategy, family position or sheer luck become successful. Different people may attribute different reasons to that success.
On the other hand, due to churning process many people also get lagged behind. That is a natural outcome which at best can be accepted gracefully, however for a few that becomes unthinkable. Unfortunately, they do not want to let go their supremacy, because they cannot reconcile with the idea of one ordinary person from their tribe marching way ahead of them. In such circumstances they are left only with one option and that is to twist the facts in such a way that they could still look the winner.
To achieve that they often resort to irrational behaviour such as playing politics, back biting, scheming, manipulating to show the other person who stole the march look dumb in the tribe.
So, they do not judge the one who has succeeded on his merit, but by their own chosen criterion and try to shame him.
I don’t know that whether other species also have some similar trait as do Homo Sapiens have.