Your first example hits the nail on its head. I use code history all the time to understand the context in which a bug or weird looking piece of code was introd

Your first example hits the nail on its head. I use code history all the time to understand the context in which a bug or weird looking piece of code was introduced. If the developer who wrote it isn't around anymore, or can't remember the details, then this information is really crucial to gain confidence that changing or removing the code won't just introduce another obscure bug because you didn't understand the reasoning behind it.