[EagnaIonat]

> They know the code best.

Two major issues occur unless they have experience.

1. The developer will often have what is called "Acquired knowledge". That is information that is relevant but isn't in any of the files and the developer assumes other developers know what they know.

2. Often is the case that there is more information required that doesn't sit inside the code and is not evident to get the program to work. Quickest way to find that is to get a newbie on a clean machine to follow only the instructions.