They create personal tragedy and lasting trauma, and these far outweigh any educative effect. We live on the skin of a Kraken which can wake and plunge to the depths with all of us on her back. But there is a strong element of randomness and of unpredictability about it. Randomness and indeterminacy are at the heart of sub-atomic reality. Quantum physics tells us that fundamental particles can undergo sudden and unpredictable change without cause.
Unpredictability intrudes at larger scales where most systems are fluid and chaotic.
The movements of ocean waves or clouds are chaotic and unpredictable even over the medium term. On longer time-scales the movement of currents in earth's magma, of stars in the arms of galaxies, or of galaxies and clusters of galaxies, are chaotic. We humans live in a quiet storey of a dangerous and turbulent tower block. At bigger and at smaller scales of space and time, events are governed by randomness. Outcomes are uncertain, risk is endemic, and all sensible bets are off.