1. Learning new languages isn't hard once you've done it a few times. The people most interested in stuff like this don't see that as a meaningful cost, and man

1. Learning new languages isn't hard once you've done it a few times. The people most interested in stuff like this don't see that as a meaningful cost, and many even enjoy it. 2. For certain classes of projects the future of the underlying tools aren't relevant. You may be surprised how many projects either don't have a long projected lifetime, or are expected to have a long deployed life with little to no updates or rebuilds. 3. The only way a language can become mature and lasting is for it to survive those first "5 years" (as you put it). Somebody has to be out on the front lines, putting it through its paces, and contributing to the community that makes it last. 4. These new languages often act as unofficial testing grounds for ideas that later fold back into more established languages. We're in an age of extensive research and innovation in practical languages and tools. It's kind of exhausting sometimes, when you try to keep up on it all (or have a team that tries too), but it's an incredible boon to the industry as a whole.