Design consistency implies that the design or geometry of a road does not violate either
the expectation of the motorist or the ability of the motorist to guide and control a vehicle in a
safe manner. Keeping a roadway consistent in design is important because it is believed that
motorists make fewer errors at geometric features that conform with their expectations than at
features that violate their expectancies. An inconsistency in design can be defined as “a
geometric feature or combination of adjacent features that have such unexpectedly high driver
workload that motorists may be surprised and possibly drive in an unsafe manner.”(