ism
ism - a practice, a process.
Life is some combination of acting and being acted upon. The circumstances of those actions differ for everyone.
I believe so to does the tendency of the individual: some are more prone to acting, seeking experience and then reacting to how the external world acts back. Others, like myself, are more reactive to the outside world, acting after being acted upon. Cautious at first, perhaps more hesitant to experience. It's not a dichotomy but a complex spectrum.
Since my youth I was quite cautious. I do not know why. This is why I suggest it is an individual's tendency. Even if we change as we age, before we've had much time to learn, we still have different tendencies toward action.
These early years of experiencing the outcomes of our tendencies have great potential to influence our thoughts on the nature of life. Again, these experiences and influence vary greatly from person to person. And again, this variance is likely from mixture of factors ranging including elements of randomness, skill, nature, etc.
For some, our decisions are rewarded: some who are assertive and take action may seize limited opportunities, gain knowledge and skills quickly, broaden their exposure to people, places, and practices that benefit them. Others who are more slow or cautious to act may avoid risky actions that did not payoff for early takers,