As an example of how fast things can change on the water; I was captaining a smallish day boat (48'), and had tied up to a "maintained" mooring, on a trip with 25 or so passengers, regular windy day by Maui standards. While the pax were in the water, mostly snorkelers, I was helping out with something or another on the lower deck (controls were on the fly bridge). I suddenly noticed a distinct change in the way the boat was rocking. I stood up looked at the deckhand, and we both instantly knew we had lost the mooring. I ran up to the bridge, deckhand got people that were actively climbing the ladder on board, and yelled at everyone else to move away from the vessel, other deckhand pulled in the mooring line. In that time, maybe a minute, we had drifted close enough to another vessel that I made contact, as I was trying to pull away, causing about $10K in damage between the two boats.
The mooring had pulled up from the bottom. If I was another 15 seconds slower, we would have been pinned to the bow of the catamaran I slightly hit, and I can't imagine the damage and/or injuries that would have caused.
Why anyone would moor close to an island, over night, without a night watch/captain is utterly beyond me. I made it out by less than 15 seconds and I was awake, active, paying attention and had two deckhands that were spot on and saved my bacon. Not having a night watch isn't even a cost saving measure, it is a complete dereliction of duty and self preservation. All it would have taken was a broken line or poor anchor position and the boat would be on the rocks or blown into another vessel at anchor. Doesn't even take a fire to have a nightwatch to be a valuable ROI. I can guarantee you TA have experienced a loss of anchor at SOME point in their history. They were just, apparently, unwilling to learn from close calls.