Compilation is, at its core, an automation for quality. That is, it's doing work that is intended to polish and refine its source input to some end. If you don

Compilation is, at its core, an automation for quality. That is, it's doing work that is intended to polish and refine its source input to some end. If you don't need the compiler, you can write machine code in hexadecimal directly, like the old days - that's really "coding" a program. But as a practical matter, we do need it - we want more organized methods of coding with more static checks. And then it's a question of, well, how much? Can we automate even more of it? And we don't know those answers but we keep pushing the boundary a little farther as hardware progresses, and we also have a gradual creeping up of source code size as more and more features work their way down the stack towards being shared, reused code, so compilers always find ways to be slower. Work in an older compiler on newer hardware and it'll feel fast.