I think there's a very real part of that which is because Microsoft charges for people to get certifications and how to handle their operating system. If it was documented really well and easy to work with at a low level, then they wouldn't be able to sell any of their training would they?

This is how I feel about every single vendor that I work with. Specifically designed to be obtuse and difficult to understand so that after sales services must be purchased in order for the product to be usable.