Hmmmm ... If you take a look at Barry Boehm's classic Software Engineering Economics (which cost me an horrendous £35 second hand) on page 40 he shows the "Cost of Change curve".
Now, I've often wondered what a "change" actually is. This is one of the reasons that I bought the book.
On page 39 he says that the cost of change shows the
"... the relative cost of correcting software errors (or making other software changes) as a function of the phase in which the corrections or changes were made".
So now you know.
