na_0038: Levels in Stateflow charts
The number of nested States should be limited, typically 3 per level. If additional levels are required, use sub-charts.
Incorrect: Level_4_a and Level_4_b are nested more than 3 deep
Correct: The 4 levels are encapsulated inside a subchart
By Task > Modeling Standards for MAAB > Stateflow > Check nested states in Stateflow charts
For check details, see Check nested states in Stateflow charts (Simulink Check).