Of course if it really stops growing, then it will die...

Not that I have any particular disagreement with your overall point here, nimdokk; but I strongly disagree with the meme that "if it ain't growing, it's dying". There's a third possibility: sustaining. And in many scenarios sustaining has significant advantages over growing (not to mention, over dying). To take just one example from biology: humans stop growing at some time around 20 years of age* but we don't really start dying until maybe 70 or 80*. Sure, adolescence has its perqs; but, all things considered, I'm quite happy to be an adult.
* The exact ages don't matter; let's not split hairs.

like any other language in the world - take Latin for instance

Um, that's not why Latin died.