Have you ever met someone who is extremely unpleasant? Bitter, manipulative, angry, lazy, the sort of person who creates a perfect storm of bullshit that you do everything to avoid, preferring to watch from afar in shock at their behaviour towards everyone, and the world around them.
I've known some people who are like this across the entire spectrum of their life. They don't just lash out on a bad day; every day is a bad day for them. Everyone and everything is to blame for even the slighten grievance.
Rewind 30,000 years. Hunter gatherers, tribal thinking, groups coordinating for survival. Do you think the group would tolerate the existance of such a person in their presence, given it would threaten their survival? They'd receive a sharpened rock repeatedly to the back of the head until all life has left their body. The risk of doing otherwise is too great.
This all out shitty personality is a new phenomenon. I've no doubt some absolute bellends survived in the "good ol' days", but they would have had to have worked with a pack of bellends, likely stealing, murdering, and raping to survive and reproduce. They would survive in much fewer numbers than the number of people who can survive in today's world being a piece of shit.
With our decreasing social bonds, and incredibly unequal society we live in, the level of burden on parents drastically increase to raise children, and as the saying goes, it takes a village to raise a child. That truth has been ignored for some generations now, and the world is moving in the opposite direction.
If a parent was born unlucky, with the wrong family, and nowhere else to turn, the chances of them finding a way to mitigate this bad luck are greatly reduced, with the effect being not just mediocre parenting, but down right cruel parenting. The child is at risk of becoming an outlet for externalised negativity as the parent looks for a coping mechanism for their bad luck. The child is left to continue on this bad luck rhythm, with their own opportunities for improvement greatly reduced. Entire lives, start-to-finish, with nothing but repression, bad luck, and no-one wanting to touch these people by the time they reach any level of maturity. We all turn a blind eye.
Some time ago I read about a group of young bull elephants that were murdering rhinos. It turns out, some time in their youth, these bull elephants bore witness to the group they were part of being systematically hunted down for their ivory. Without a clan, there was little guidance as they reach maturity and deal with an unforgiving world, maturity, hormones, and likely trauma. So with no direction the result was aimless violence.
Time and time again, when reading about the past of serial killers, there are horrific stories from their childhood, and no guidance or supervision as they get older, with an escalating violent outlet for their repressed and poorly understood emotions.
Whilst these examples could be explained away in isolation with some light mental gymnastics, the volume of samples of a lifetime of bad luck leading to externalising negativity is hard to ignore. It's all around us, in society, in nature, every day.
It's convenient to say to yourself "what an asshole" and to dismiss an entire existance of misery that has led up to that point. It's convenient to tell yourself that this person "had it coming" when life treats them poorly. When they don't seek out opportunities for improvement that's on them.
It's easy to take the high ground when luck hasn't been against you since the moment you were born. It's easy to say we should each look after our own lot, and blame people for their damaging behaviour. When you have spent your childhood with good role models who are loving and not bitter towards the world, and seen the beauty that life can bring from a young age, it's easy to look at the hardships knowing things will get better. When your life has started out shit, through no fault of your own, and this has limited the amount of value you can see in your life, it becomes much harder to deal with even small misgivings because that small misgiving has never had its beautiful counterpart.
If a small thing can consistently cause certain people to blow their lid, then the obvious perspective is that this isn't about the small thing in isolation, it is about the thousands of cuts they have already received, with no respite. Life fucking sucks when it has weighed you down from the start. You lose out on education, guidance, perspective, role models, wealth, love, the lot. And with this loss comes a loss of vision of what the word humanity means. Life really fucking sucks for some people, consistently. When was the last time you, as the good person that you are, really invested your time in dealing with a shitty person with a shitty life? When did you show them what humanity could be? Was it not easier to simply say to yourself "god that person's a piece of work" and avoid them at all cost, avoid any level of personal responsibility? It's not your fault, or your problem, after all. The self-purpetuating cycle continues.
At the top of the luck totem pole it's a very hard pill to swallow to admit that life is incredibly unequal, unfair, and that your happiness and their misery comes with the same amount of determination and hard work. In fact, the hardships faced when dealing with a challenge in your life, are vastly, vastly easier to handle than a life of repression and bad luck. You have the fortune of seeing it with a temporal perspective. When, from childhood, with no guidance, no help, no humanity, no training, and deeply negative experiences, you apply yourself and get beaten down harder than those who have luck on their side, and the unfairness can be felt, but no-one is explaining it to you, no-one is helping you, and your perspective has been stunted just like the rest of your life, it's very difficult not to become bitter. Even a smart person born in to repression will never gain that perspective, because it is never once felt.
If your life has its ups and downs, consider yourself lucky.