A somewhat lengthy but very interesting talk about the tradeoffs for language design and evolution.
[CppCon 2016: Bjarne Stroustrup "The Evolution of C++ Past, Present and Future"](https://www.youtube.com/watch?v=_wzc7a3McOs) In particular the part about direction https://youtu.be/_wzc7a3McOs?t=51m29s, and the section about tradeoffs for new features https://youtu.be/_wzc7a3McOs?t=30m16s.