In one of my previous positions, I and a team of other people had to create a tool that would basically verify Bill of Material data and compare it to new product code Bill of Material data, all done semi-automatically. We already had a base version of the tool that would need to go through the change control process, so every time we found something to add or features that were requested which were critical, we would write them down in a shared document. Once a sizable list was made, we would go one by one implementing the changes/new features. Keeping this list was greatly helpful for us as at one point after the new revision of the tool had been sent out, a user found an error in one of the data streams there. When they were explaining the error, we could not pinpoint exactly what they were talking about off the top of our heads, but once we went back to that document that had all of the implemented changes, we were able to see what had gone wrong and remediated it quickly. If we had not made a log of all of the changes that we had made, it would have been a difficult and time consuming process to go through the tool and figure out where we had gone wrong. A little bit of documentation definitely goes a long way.