Despite the relatively high moisture absorption of the transitional wall systems of the early 20th century, many of these walls survived well with minimal attention for many decades. The transitional walls were primarily constructed of stone and mortar that could remain wet without rapid deterioration. The transition from masonry load-bearing walls in many cases meant a transition to glass, now one of the most common cladding materials. The quintessentially brittle material, glass has introduced its own set of challenges. Breakage can result if the design does not accommodate this differential movement.
Bad things happen to some good, even great, buildings.
Sometimes good buildings fail because their designers have pushed the limits of technology in order to create something new. As an example, Frank Lloyd Wright's Fallingwater is now undergoing structural repair to its famous cantilevers. Sometimes good buildings fail because of a defect in a common material or component. Initially, many design professionals thought the reason for the breakage lay in the fact that the tower swayed excessively in the wind. Although it was indeed swaying substantially, this was not the reason for the glass breakage.