> I don't get why it seems like languages are designed for convenience then later down the road billions of hours are spent trying to get better performance. B

> I don't get why it seems like languages are designed for convenience then later down the road billions of hours are spent trying to get better performance. Because CPUs are so fast there is usually no need to worry about performance and clarity of code and convenience is more important. Also you have to remember that Python "grew up" from early 90s through early 2000s. That when most CPUs were not multicore and CPU speeds were doubling every year almost. You could write something in Python, and in a few years, it would speed up just by going to a better hardware. You had the alternative of "here is 2000 of lines of C++ with templates, pointers, references, inheritance, constructors of various types, kind of meh standard library" vs "here is 500 lines of Python that you can read, understand and fix in much less time". Python was slower but that's ok. Getting faster machines was easier and cheaper than than work-hours poring over bugs and segfauls in the C++ code. The one reason we talk about Python and speed is because it was widely adopted and in some cases companies wanted more "speed" from it. Then multi-CPU machines become commodity and there was more talk about the GIL and such.