Reduces the number of lines of code thus reducing the number of bugs in the system!

Makes validation rules available as data thus makes maintainence easier and bug fixing turn around times short

This pattern is an overkill if the number of screens in the system is not significant. The benefit of code size reduction will be offset by the size of the rule engine and the other associated objects in the pattern.

The complexity of the DataStore and the RuleEngine increases as the complexity of business validations increases.

The ConcreteDataStore and the RuleEngine could degrade system performance if poorly written. Since this is part of the user interface experience of the user, poor performance will be clearly and immediately visible as a system flaw.