Likelihood of change and cost of change are different. A codebase which is very large is, all other facts held equal, much harder to change. While a small, earl

Likelihood of change and cost of change are different. A codebase which is very large is, all other facts held equal, much harder to change. While a small, early codebase may iterate very rapidly, drag will increase. The question is whether in the expected lifetime the higher upfront cost of providing tests pays off in average velocity.