Ken Thompson on Fragile Code
Some people write fragile code and some people write very structurally sound code, and this is a condition of people. I think in almost any language you can write fragile code. My definition of fragile code is, suppose you want to add a feature–good code, there’s one place where you add that feature and it fits; fragile code, you’ve got to touch ten places.
– Ken Thompson, Coders at Work, p. 467