A complex software much much easier to break accidentally. While one character can break "hello world" is not something one would do while trying hard not to br

A complex software much much easier to break accidentally. While one character can break "hello world" is not something one would do while trying hard not to break it. And potential bugs in a simple application much more likely will be cough during a review. For a complex application no-one have a good mental model to predict what a given change would do reliably. For a simple one it's possible.