Code Smells
Code Smells / Dispensables / Lazy Class

Lazy Class
A Lazy Class smells represent classes that are under-used.
If a class is rarely used, it can impede development by increasing the complexity of the codebase. Such a class might be unnecessary, and it’s functionality could be made a part of another class.
Lazy Class is the opposite code smell to Large Class.
Books about code smells
Learn to write better smelling code.

Refactoring: Improving the Design of Existing Code

Code smells: A Predictor of Remarkable Quality Improvement

Clean Code: A Handbook of Agile Software Craftsmanship
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