The interpretation of non-conformance depends on the purpose of the model.
If the model is intended to be descriptive, then discrepancies
between model and log indicate that the model needs to be improved to capture reality better. If the model is normative, then such discrepancies may be interpreted
in two ways. Some of the discrepancies found may expose undesirable deviations,
i.e., conformance checking signals the need for a better control of the process. Other
discrepancies may reveal desirable deviations. For instance, workers may deviate to
serve the customers better or to handle circumstances not foreseen by the process
model. In fact, flexibility and non-conformance often correlate positively. For exam-
ple, in some hospitals the phrase “breaking the glass” is used to refer to deviations
that are recorded but that actually save lives. Nevertheless, even if most deviations
are desired, it is important that stakeholders have insight into such discrepancies.