How does a split work at an exclusive gateway (XOR)?

In an exclusive process pass, a process folder at a branch is only forwarded via one outgoing flow. The decision as to which branch is activated can be modeled in the BPMN process diagram using probabilities or events:

Probabilities

As soon as a process folder is activated at an exclusive gateway with multiple outgoing gates, a process folder with the process number of the activating process folder is forwarded via a gate. Forwarding is based on probabilities by default. Probabilities can be defined for outgoing sequence flows (Simulation attribute type group, Probability attribute). The sum of the probabilities of all sequence flows should be equal to 1.

If this is not the case, or if no probabilities have been specified, the following rules apply:

Events

An event-based exclusive gateway can be modeled by linking (Receive) tasks or intermediate events to it via sequence flows. A process folder arriving at a gateway waits until a message is received at one of the (Receive) tasks or until one of the events is triggered. As soon as this happens, a process folder is forwarded to the subsequent object via the corresponding sequence flow.