Whenever the conceptual model involves a greater complexity, we use the business-object pattern. This high complexity may be because the BO uses a combination of other objects and has complex business logic, such as validation rules. So, separating this business logic from the rest of the application is required (data persistence would be an example of this).

Not implementing this pattern can lead to problems, such as reducing code reusability. As a consequence of this, there are several possible solutions that make code maintenance time-consuming, as it would lose the uniformity that comes with using design patterns.