Why invent a new language? It's not as if there's a shortage of them.
But with a new programming language comes a new way to look at all the problems that developers, IT admins, and everyone in between face. To that end, the new languages most worthy of your attention are the ones that bring a novel perspective to an existing problem.
Not all of that is about the language; sometimes it's about the environment a language provides. Google's Go and Mozilla's Rust didn't simply offer new syntax, but also new toolchains and strategies to manage projects.