I was doing some simulation tests and edited the percentages of my gateways. The gateway I defined as 50% out of each of the two outgoing flows. For some reason, my 100 outgoing instances are not split in 50/50 but in 43/57 instead.
The simulation of a decision on a XOR-Gateway is done randomly. For every single run / token passing through this element the system generates a separate outcome dependent on the given probability.
It is like, if you would flip a coin. The probability for heads or tails is fifty-fifty but after 10 flips there could be another result then fife heads and fife tails.
KBA , BPI-SIG-PM-MOD-EDT , Graphical Editor for SAP Signavio Process Manager , How To