About Model Validation

It is a best practice to validate your rules before you calculate them against a data POV. Model valiadation helps maintain the integrity of rules that may have been impacted by things like changes in dimensions definitions or incomplete rules.

Errors can be introduced when members directly referenced in your rules are renamed or deleted during a dimension change. If you delete members from dimensions that are referenced in existing rules, the rules can't run.

In addition, rules must be fully defined. This means that the source, destination, and target definitions for each rule must include members from every dimension.