Data inconsistency in validation prerequisite "&", step "&"

What causes this issue?

During ABAP code generation a data inconsistency was discovered in the
&V1& validation. The data inconsistency concerns the validation
prerequisite.

System Response

The corresponding ABAP code was generated for the Boolean statement,
but it could be, that the valuation of the statement could lead to an
unexpected result.

How to fix this error?

Check and correct the &V1& validation (step &V2&) using the validation
maintenance.

Error message extract from SAP system. Copyright SAP SE.