The guys behind Sneaky Bastards have published a "2014 Manifesto" on the stealth genre. And whether you can even call it that. If you enjoy any part of a game where you're sneaking around, go read it.
I like my games to have a mix of action and stealth. And that comment
Pure stealth for me is when there is no way to permanently eliminate (kill or knock-out) the threat (the reason for being stealthy) – in a way that allows non-stealthy behaviour to be adopted”
Just seems silly to me. What is the point of stealth if it isn't sneaking up behind a guy and snapping his neck. Take a look at Metal Gear Solid if you want a fantastic stealth game. You could kill people in that game, and then hide the bodies. You could go that entire game never setting off an alarm.
I feel like a purely stealth game would have to be something of a puzzle game then. With no action to space out the stealth, it may get a little tiresome.