Because the only way to learn the answer to that question, is to learn why people are using the other languages, which in turn, likely means researching them an

Because the only way to learn the answer to that question, is to learn why people are using the other languages, which in turn, likely means researching them and learning them for yourself. To answer your question more on point, the first thing you'll find is other languages add much, much more safety into their language than js-node can. Indeed, that's what makes js-node as much fun as it is. But if you're a new business owner, and you have to choose between building your server backend on java/c#/etc technology, which can be rigorously checked for stability, and js, chances are high you're going to go with the languages that have such automatic checking features.