From memory I think there was 7 different warnings on the boarding ladder including do not remove this warning label

I think what it probably means is that no one should be aboard the boat while it is being winched.

In confined space/fall protection people will use almost anything they can find sometimes to raise or lower people and equipment. There are winches that look almost just like a boat winch that are used for confined space rescue or to raise and lower people/equipment. If it didn't say that its not man rated and someone got hurt using it wrong a huge law suite could result. We have to state pretty clearly on our winches and srl's if they are man,equipment, or rated for both and to what load.

What you're looking at there is several hundred thousand dollars (maybe much more) spent on an army of lawyers who shouldn't have been involved in the first place.

Same reason every US-sold wheelbarrow tire has to be stamped "Not for highway use." Common sense, and judges who believe in the value of it, are a distant memory here.