Labels are custom strings that can be assigned to choices on different positions of a choice hierarchy of a parameter. Labels are inherited from parent choices. Next to hierarchical choices they are a way to group some choices with similar properties together.
Let's assume that we will consider granting a loan to retired people and those with temporary contracts if their last year income was very high, after they provide us with some more documents. We can set the loanDecision to INCONCLUSIVE for those cases. We can do it in three ways. One of them is to define a constraint that will enumerate all choices of the employmentStatus parameter that together with a very high income are entitled for the INCONCLUSIVE decision. This is however problematic to maintain in case when we will add some more choices to this parameter in the future - we will have to remember to update the constraint. Other way is to group the choices under an abstract choice called "inconclusive". We may however have some hierarchy for choices of the parameter already and not be able to change it.
The third way is to add a label to those choices. Go to the details page of temporary work contract choice and click the Add label button under the Labels viewer. Click on the label string to change its value to potentially positive loan decision. Do the same with the retired choice. Now define another constraint named loan decision:
Now you can generate N-Wise test suite for this method and check that the value of loanDecision parameter was correctly set in all cases.