Years ago I was working for the final company to own the project for Trump Tower Tampa. The reason it didn't get built? It was to be built right next to the river. After the initial site survey the geologist weren't comfortable with the original shoring design, thus they drilled more, and still weren't comfortable. Somewhere along the line the rights to the project were sold off and the incredibly small company I worked for ended up with the rights to the project, which was eventually scrapped. Had the housing boom continued for much longer, I'm afraid it likely would have been built.