How a typical Software development company keep records of client requirements? For example:
A) One day client asked us to add a tracking code to his website.
B) Another day same client asked us to add a different code but same vendor code in a separate page. This code will not work without above tracking code A).
After few months same client asked us to update the tracking code of point A). In this situation if developers take action to update point A) then point B) will cause the issue and nobody aware about it, until it causes some issue.
Given this example, can you tell me how a large organization handling this kind of situations? Are they waiting for errors to show-up in the page?