The excessive use of modes in soft controls should be avoided.
Additional Information:
Modes occur in soft controls when a display or input device is designed for more than one function. For example, a soft control that is used for manipulating multiple variables may have a separate mode for each one (e.g., individual modes for variables A, B, and C). In addition, there may be multiple modes for a single variable, each allowing it to be controlled in a different way (e.g., variable A may have separate modes for manual control, automatic control, and testing). Mode errors occur when the user believes the device is in one mode when it is in another and, as a result, performs an inappropriate input action. The likelihood of mode errors can be lessened by reducing the number of modes; if multiple modes do not exist, then mode errors cannot occur.