I’ve often heard statements like, “Why would I need to create internal documentation? The code tells you everything you need to know.” when pushing better documentation practices inside of a group I’m working with. It’s true that the code tells us what it’s doing but, like the earlier statement, it doesn’t tell you why the code is doing what it does and context is very important. Without understanding the reasoning behind past decisions, we risk similar mistakes similar to those we’ve made in the past.