This is a common pattern where two or more control flow sequences merge. In this pattern, the subsequent tasks are executed only after both sequence flows have executed. For multiple incoming tokens, there is only one outgoing token i.e. only after all incoming sequences have finished execution, will the control flow pass to the subsequent activity.
In this example, the tasks to check a received invoice and produce invoice happen in parallel but dispatch goods will only happen after the produce invoice and
check invoice have both finished.