What is Code Smell? — UK Software Development Guide

4 min readJune 2025ClickMasters Technical TeamReviewed by James Whitmore, CTO
what is a code smell

Direct Answer

A code smell is a surface indication in code that suggests there may be a deeper problem with the code's design or quality. Code smells are not bugs — the code may work correctly — but they indicate areas where the code has deviated from good design principles and may accumulate technical debt. Common examples: long methods, duplicate code, large classes, and deeply nested logic.

Code-smell in the UK

Code smells have commercial significance for UK businesses. Technical debt caused by code smells has a measurable cost: an average of 23 additional minutes of development time per hour of work for developers working in "smelly" codebases (McKinsey Digital study). For UK regulated software: code smells in security-critical code (authentication, access control, data processing) are particularly dangerous — complex, difficult-to-read security code is harder to audit and more likely to contain vulnerabilities. ClickMasters code reviews specifically look for common code smells as leading indicators of technical debt accumulation.

Get Expert Advice on Code-smell

Speak with our UK software development experts about Code-smell. Free consultation, transparent pricing, no obligation.