in memory of - John T. Smith - a fine martial artist
If one were able to know and understand the effects of ALL of the inputs: genetics & environment (nature, nurture ± past lives) that make up an individual's "causes and conditions", their behavior under any new set of circumstances would be more predictable. Even identical twins behave differently, because their inputs, though similar (if raised in the same home) are not identical. Basically, expecting a person to behave differently than they do is unreasonable.
Recently, I asked a colleague for a minor favor. It was a perfectly reasonable request that most people would expect to happen, but I had no expectations at all (due to my colleague's health). When he agreed to help, I was truly elated and happy. It was a wonderfully pleasant surprise.
Most of us have inadequate insight even into our own causes & conditions, so we should try to have an open mind, & a patient, non-judgmental attitude even towards our own behavior. I suspect that each one of us has a heavy load of stuff to process in this lifetime. Each of us has different abilities to carry out this life's task. And each of us tries our best to be gentle, intelligent, patient, as together we slowly, tirelessly, persistently all move towards wisdom.
An inspiring recent movie that you might find nurishing: