Statechart Checks : (C2057) Elements that are used in the chart are neither “in” parameter nor affected (generated or modified) internally

(C2057) Elements that are used in the chart are neither “in” parameter nor affected (generated or modified) internally

Elements are used in a statechart but are neither input parameters nor affected internally.
Error In:
Completeness
Erroneous Elements:
Events, conditions, data-items, and activities