Two services separately encode the same discount rule and now disagree. What is the central DRY problem?
Answer & explanation
Duplicated business knowledge can drift apart.
The duplicated meaning is the issue. A change to the rule creates several places that must stay synchronized. An authoritative representation can help, provided its ownership and interfaces fit the system.
The Pragmatic Programmer
Chapter 2 · A Pragmatic Approach
AI reviewed · sources pending · version 9
Generally accurate according to an AI review. Sources and this book association have not been verified.