It's not at all like that. I pay a one-time fee to BMW to get a seat warmer feature, they're not constantly improving or updating them in my car. They're in my car and they're on or off. If they break and I value them, I pay to have them fixed.

MDN is updated often and I it makes my job easier. It makes constantly evolving spec much more digestible. I'd sorely miss it if it were gone tomorrow. It's a service, not a one-off feature.