An anemic domain model separates business logic from domain objects, placing it in services instead. This leads to duplicated validation logic across use cases and poor encapsulation. Using Domain-Driven Design principles, business rules and invariants should live close to the models themselves — for example, inside factory methods like User.create(). Rich domain models improve discoverability, reduce duplication, and enforce data integrity through encapsulation. However, anemic models can be appropriate for startups, proofs-of-concept, or functional programming contexts where immutability eliminates the need for invariant enforcement within objects.
1 Impression