Each of us is born and grows up with unique strengths and weaknesses. Maybe a few have only strengths or weaknesses. Society would be better if everyone had only strengths and impossible if everyone had only weaknesses. Interactions between individuals with different weaknesses and blind spots can be lethal. We have god-like powers of procreation, productivity and creativity. The combination of personal weaknesses with god-like powers can also be lethal.
An immature response is to despise those perceived as weak whereas maturity tolerates or helps weakness. A guy I worked with had two weaknesses: he was very low ability in the job and so worried about whether he was ok with other people that he kept putting it to the test, "trying the patience of a saint" of whom there were none in that work place. A confident and out-going colleague commented, "People like him latch onto people like me."
Why are some entire lives spent without any reflection or growth in self-awareness? Since zazen is the practice of awareness, Zen trainees can become aware of their weaknesses but usually not fully aware in the time left between starting to meditate and dying. Major blind spots can remain. I used to disregard anything that I did not see as important even though it did concern the people around me. Pondering ultimate issues brought me to zazen and to a Marxist understanding of society. I now give more attention to immediate social interactions but can still get them wrong to say the least. We need more time but can only use the time that is given.