Software Design/Complexity (high-level quality)

Complexity as a high-level code quality is defined by John Ousterhout in A Philosopy of Software Design as "anything related to the structure of a software system that makes it hard to understand and modify the system." It is derived from the following qualities:

• Complexity as a primary quality
• Steepness of learning curve
• Interface size and its conceptual weight
• Naturality
• Code clarity
• Code size
• Easiness of change
• And other qualities.