That's the problem though - code is not enough for understanding. Very well-written and documented code can be, but it's not a given. And the complexity grows exponentially the more of the code there's.
Unfortunately, many managers think the way you describe, while discounting the intangible knowledge that's only in the heads of engineers, and leaves with them. So they treat engineers as disposable units while thinking that possession of the code will guarantee transfer of knowledge.
That's the problem though - code is not enough for understanding. Very well-written and documented code can be, but it's not a given. And the complexity grows exponentially the more of the code there's.
Unfortunately, many managers think the way you describe, while discounting the intangible knowledge that's only in the heads of engineers, and leaves with them. So they treat engineers as disposable units while thinking that possession of the code will guarantee transfer of knowledge.