Lazy Class

This smell occurs where a class is not doing enough i.e. it does not realize a concrete responsibility. Fowler says that "Each class you create costs money to maintain and understand. A class that isn't doing enough to pay for itself should be eliminated."

Related smells: Unnecessary Abstraction

Reference

M. Fowler, “Refactoring: Improving the Design of Existing Code”. Addison-Wesley, 1999.