For sequence flows that follow an XOR (data-based) gateway or an inclusive gateway, a value must be set for the Condition attribute.
If the value Expression is set in the Condition attribute, the diamond symbol is to be placed at the beginning of the connection.
If the Condition attribute is set to Default and the source object is a function, the \ (backslash) character is to be placed as a symbol at the beginning of the connection.
The \ (backslash) symbol must not be placed if the source object is a gateway.
No condition should be set if the source object is one of the following symbols:
Event-based gateway
Complex gateway
Parallel gateway
Start event
Intermediate event
If the Default value is enabled in the Condition attribute for a sequence flow connection, no condition must be specified.
The Condition attribute may be set to Default if the source object is a function or an XOR (data-based) gateway.
If the value Expression is set in the Condition attribute, the Expression attribute must also be specified.