Smart risk assessment includes moving indoors during a lightning storm or getting out of the water when a shark has been spotted. Sure, the odds of being struck by lightning or bit by a shark are extremely low, but it only has to happen to you once.
Yes, but smart risk assessment does not include staying inside whenever it is cloudy or never swimming in the ocean. The number of kids actually abducted by a stranger is about 200/year, IIRC. Killed by a stranger, 50. Those are pretty small numbers.
(As for shark attacks, boy, THOSE numbers are REALLY tiny! I never worry about sharks, though I don't surf.)
BUT! I am paranoid mom of the year when it comes to water safety. Because drowning happens. A lot. I have seen a couple of close calls with young kids already. Brrr.