Is this THE reason? I don’t know about that, but the findings in this study correlate with what I’ve seen as an adult:
“Yet according to a study published in Evolutionary Psychology, risky play–the kind where someone actually could get hurt–is good for kids. Researchers suggest that the fear kids experience when climbing at great heights, being near a cliff or handling a knife keeps them alert and careful and teaches them how to cope with potentially dangerous situations. And over time, mastering such scary situations has an “anti-phobic” effect which results in lower levels of anxiety overall.”
As an adult, I know that I experience much less anxiety than I used to because I’ve been forced to stretch myself, and have the confidence to know I can come through uncomfortable situations, like traveling to a foreign country or moving across the country by myself. I assume as children we need to be “scared” and come through it in order to build up that same level of self-confidence.
Maybe we can find ways of doing that without people getting seriously hurt though. What do you think?