PowerDesigner provides default model checks to verify the validity of transitions and flows.
| 
                             Check  | 
                        
                             Description and Correction  | 
                    
|---|---|
| 
                             Transition / flow without source or destination  | 
                        
                             The transition or flow has no source or destination. Manual correction: Select or create an object as source or destination. Automatic correction: None  | 
                    
| 
                             Useless condition  | 
                        
                             If there is only one output transition/flow, there is no reason to have a condition or type on the transition/flow. Manual correction: Remove the unnecessary condition or type, or create another transition/flow with another condition or type. Automatic correction: None  | 
                    
| 
                             Missing condition  | 
                        
                             If an object has several output transitions/flows, or if the transition/flow is reflexive, each transition/flow must contain a condition. In a statechart diagram, a transition must contain an event or condition. Manual correction: Define a condition, or create a synchronization to specify a parallel execution Automatic correction: None  | 
                    
| 
                             Duplicated transition between states/ Duplicated flow between activities  | 
                        
                             Two parallel transitions (with the same extremities) must not occur simultaneously, but must rather be governed by conditions (and, for transitions, trigger events). Manual correction: Change one of the trigger events or conditions Automatic correction: None  |