Code does not deteriorate if it is not used.Martin Fowler
The first step in refactoring is to ensure you have a solid suite of tests.Martin Fowler
Refactoring changes the programs in small steps knowing that after each change we can still run the system.Martin Fowler
When you find you have to add a feature to a program, consider the possibility that what you actually have to do is to refactor the program.Martin Fowler
Tests not only detect the presence of errors, but also their absence.Martin Fowler
Once code meets the needs of the task, it is not necessary to improve it.Martin Fowler
Any fool can write code that a computer can understand. Good programmers write code that humans can understand.Martin Fowler
If the code and the comments disagree, then both are probably wrong.Martin Fowler
Kitting the code into a nice, neat, modular form is a nice, incremental refactoring that makes sense and should be done gradually.Martin Fowler
Refactoring is a disciplined technique for restructuring an existing body of code, altering its internal structure without changing its external behavior.Martin Fowler