Why put something that provably is never used in there at all?
It's important not to confuse "never used because it's useless" and "never used because nobody knows about it".
Of the items in the Windows 8 "Home" tab that fewer than 84% of people use, half of them appear to be new features and half are features that exist in Windows 7 but don't appear in the toolbar or any context-menu, have no keyboard shortcut, and aren't documented in the help files. People who used these features in XP could be forgiven for thinking Microsoft removed them in Vista.
Why not put context-aware stuff in a context aware tab like the image tab in Word
They do. In their blog post they have examples of context-sensitive tabs for libraries, drives, and images.
It's important not to confuse "never used because it's useless" and "never used because nobody knows about it".
Of the items in the Windows 8 "Home" tab that fewer than 84% of people use, half of them appear to be new features and half are features that exist in Windows 7 but don't appear in the toolbar or any context-menu, have no keyboard shortcut, and aren't documented in the help files. People who used these features in XP could be forgiven for thinking Microsoft removed them in Vista.
Why not put context-aware stuff in a context aware tab like the image tab in Word
They do. In their blog post they have examples of context-sensitive tabs for libraries, drives, and images.