This sign marks the border between Hualalai Resort and one of the public beaches there. It’s the equivalent of prescription drug warnings that taking them might turn you into a four-armed, paranoid psychopath.
Here, the dangers include man-o-wars, sharp coral, slippery rocks, sudden drop-off, dangerous shorebreak, high surf, and strong current. Oh, and there’s no lifeguard on duty. Well, no wonder, they’d have to be crazy to enter the water there.