The hose has a single clamp directly at the sink, the connection "fails" (because of whatever physical or mechanical event) and the hose "flops" down. The former "top" is now on the "bottom". The boat is on its way there, too ;^))).

Hadn't focused on it myself as a "risk" -- interesting observation, Jeremy. At the least, I'm going to eyeball all the conditions.

In the case of a thru hull above the water line when the boat is "at rest", the boat could have that same line pressurized by motion (forward, or heeling, or whatever). On a long passage, the classic story starts "I went down below and discovered the water was above the floorboards..."

( Having a small leak which you don't notice because the bilge pump removes the water HIDES the problem. That's why a counter is most useful. If you see that it's cycled a bunch of times, you have to find the reason(s). Not having a counter makes it harder to notice that the bilge pump was forced to work. The pump, after an extended period will eventually fail. If there's a power outage, the batteries will eventually discharge if you're on shore power. If you're at a mooring, you'd have little if any sign or help after your batteries are drained.)