People naturally have a survivorship bias. Thomas Ligotti has this great quote about why people, most people, are Optimistic (specifically with existence), tha

People naturally have a survivorship bias. Thomas Ligotti has this great quote about why people, most people, are Optimistic (specifically with existence), that this is all okay, and nothing will go wrong, and that when things do go wrong, it'll be okay in the end “The point that in the absence of birth nobody exists who can be deprived of happiness is terribly conspicuous. For optimists, this fact plays no part in their existential computations. For pessimists, however, it is axiomatic. Whether a pessimist urges us to live “heroically” with a knife in our gut or denounces life as not worth living is immaterial. What matters is that he makes no bones about hurt being the Great Problem it is incumbent on philosophy to observe. But this problem can be solved only by establishing an imbalance between hurt and happiness that would enable us in principle to say which is more desirable—existence or nonexistence. While no airtight case has ever been made regarding the undesirability of human life, pessimists still run themselves ragged trying to make one. Optimists have no comparable mission. When they do argue for the desirability of human life it is only in reaction to pessimists arguing the opposite, even though no airtight case has ever been made regarding that desirability. Optimism has always been an undeclared policy of human culture—one that grew out of our animal instincts to survive and reproduce—rather than an articulated body of thought. It is the default condition of our blood and cannot be effectively questioned by our minds or put in grave doubt by our pains. This would explain why at any given time there are more cannibals than philosophical pessimists.”