Async process never ends from time to time

public class AsynchTestDelegate implements JavaDelegate {
	  protected static final Logger log = LoggerFactory.getLogger(AsynchTestDelegate.class);

	@Override
	public void execute(DelegateExecution execution) throws Exception {
	    log.info("TestDelegate called for execution: "+execution.getCurrentActivityName()+" executed: "+executed);
//	    Thread.sleep(20);
	}
}

public class ParallelGatewayActivityBehavior extends GatewayActivityBehavior {
  protected static final BpmnBehaviorLogger LOG = ProcessEngineLogger.BPMN_BEHAVIOR_LOGGER;
  public void execute(ActivityExecution execution) throws Exception {

    // Join
    PvmActivity activity = execution.getActivity();
    List<PvmTransition> outgoingTransitions = execution.getActivity().getOutgoingTransitions();

    execution.inactivate();
    lockConcurrentRoot(execution);

    List<ActivityExecution> joinedExecutions = execution.findInactiveConcurrentExecutions(activity);
    int nbrOfExecutionsToJoin = execution.getActivity().getIncomingTransitions().size();
    int nbrOfExecutionsJoined = joinedExecutions.size();

    if (nbrOfExecutionsJoined==nbrOfExecutionsToJoin) {  //HERE!!!!!!!!

      // Fork
      LOG.activityActivation(activity.getId(), nbrOfExecutionsJoined, nbrOfExecutionsToJoin);
      execution.leaveActivityViaTransitions(outgoingTransitions, joinedExecutions);

    } else {
      LOG.noActivityActivation(activity.getId(), nbrOfExecutionsJoined, nbrOfExecutionsToJoin);
    }
  }
}