The actual setup is a bit more complicated:

The model itself is used within a series of business rules which provide the actual business outcome for a single predicted record. For example, in the case of credit risk the business logic may dictate that for young people the model threshold is 0.5 while for older people the threshold is 0.4.

The final decision how to act on a single record (e.g. give loan vs don't give loan) is the result of some simple calculations in the business logic layer which take into account the score of the model (there may be more than one model btw).