Surface defects are small-scale, discontinuous imperfections in the surface smoothness. Early glass was rarely transparent and often contained impurities and imperfections. Borescopes are mostly used in nondestructive testing techniques for recognizing defects or imperfections. When complete, a plane is rigorously inspected to search for imperfections and defects. At the very least, they cause internal work hardening and other microscopic imperfections. Depending on edge imperfections this can directly scatter light into the cavity. Spark creates deep characterisations which are realistic in their human imperfections. Old glass is recognised by its imperfections ('ream') which result in optical distortion. Marks on the face transfer into imperfections in the blacksmith's work. In essence, all are equal by virtue of sharing the same imperfections. The Leica lenses have some involuntary imperfections. The league has regularly modified its rules to counter perceived imperfections in the game. All of these motivations for FDI are built on market imperfections and conflict. She also realizes her own imperfections and criticalness towards others. She criticized their physical imperfections, including Ronnie's small stature and Roxanne's crooked teeth.