This question comes following an incident which we had last week in a bay on the north of Hvar island off Croatia.
We had moored to an established mooring buoy (provided by a restaurant) which was slightly unusual as it was a large warp under the buoy (with a loop for the front cleat) and a thinner line which ran to a tree ashore attached to the stern, to keep the boat aligned (this allowed 2 boats to be moored in a smaller space).
There was a firm wind and a bit of swell in the bay, but nothing particularly unusual.
After returning to the boat following a nice meal, we were readying to go to bed, when the crew on the boat next to us started shouting our boat name. The large warp to the sea bed had broken (at its attachment to the sea bed) and we were hitting the rocks by the time I was up the companionway.
I was lucky enough to b able to drive the boat off the rocks using the engine, having only damaged one of the rudders.
My question is, does anyone know if failure of established mooring buoys is often experienced, or were we just very unlucky?