Hi, right now I'm learning Go (to write an access control system for our makerspace). For me this is a pretty new language but currently at the point where I see quite large community and available libraries (wait, it is called a module, isn't it?).
Why? I love C language (static typing, you can shoot yourself in a leg == you can do almost anything, etc..), but C is not suited to write this kind of application. I also like PHP - large community, libraries, large OS systems written in it... But I miss some C features and getting bored by having dozens of dependencies for a simple project. Python - is slow (yes, can be tuned somehow, but brings more work to do) and I do not like the syntax and I miss brackets. For me, Go seems like a way to go from now on.
So, to sum it up - for me a new language is a way to solve some set of problems much easier (and sometimes more efficient and/or secure) than with an existing language. I wouldn't be happy if I had to write anything larger than hello world in assembly :)