So, in Windows 8 MS removes the Start button along with the menu.
In Windows 8.1 we get the Start button back, but no start menu. It's a sad/blue story indeed.
In Windows 8.2 we get Start menu added to the Start button.
The progress is staggering.
The Start Menu is not coming back. Ever.
The Start Button was brought back for a simple reason: conduit.
You see, the "Start Button" was actually placed in the charms bar, only visible when you swipe form the right. This is more easily identifiable to users with touchscreens than those with M+K. To help with this, the Start button is being brought back for it to serve as a both literal and metaphorical conduit to the Start Screen, which is, the "new" Start Menu.
So don't think of the button being brought back as the Start Menu progressively making a come back; it is being added back for the sake of familiarity.
The change was actually not made by the Windows team. Instead, it seems it was forced onto them by their higher-ups. This is particularly sad, as it shows you how detached teams are in Microsoft.
Lastly, I was told the the button and boot-to-desktop is all being brought back due to businesses and the enterprise's reluctance to upgrade (arguably where Microsoft makes the most money other than OEM licences). Not the consumers.