I agree with all that has been said, but I will add that all anchores should have a swivel attached from the anchor to the chain. Most Commercial fisherman have swivels on there anchores. It amazes me when I walk down a marina the number of boats that don''t have swivels on.
I carry three sizes of swivel as a crew member and if the owner or skipper does not have a swivel on the anchor I convince him to put one on. It prevents the anchor twisting out when the load comes on.
I have found that most anchores that fail to hold when the load comes on is due to twisting.