Why is a barrier island a poor location for a house?

A barrier island is a poor place for a house simply because there is nothing else between it and the power of the ocean. This includes wind, waves, and flooding. A barrier island is called a "barrier island" simply because it acts as a barrier to the mainland behind it, as in the case of Assoteague being a barrier to Chincoteague in Virginia and the Outer Banks islands in North Carolina protecting the natural coastline.