Why isn't 6 face buttons a standard?

[d21lewis]

ktay95 said:

Wildcard36qs said:

I've always wondered, can those rear buttons be additional buttons? Or do they have to be mapped to existing ones?

Mapped to existing buttons sadly

On the plus side (I don't have this controller but I assume it's still applicable), the Xbox One lets you remap the buttons to whatever you want in the main settings menu. If you want one of those paddles to be something else, I'm sure it's an option.