[apdinin]

I have trouble accepting the general premise of the question. Not the $100m part... even a $100k job or a $10k job... doesn't matter. It implies that the program being developed has a definitive "done" moment. But software (at least software in constant use) doesn't really get finished. So you build, and you expand, and you rebuild, and new things happen that change your approach and new tech gets developed and your software changes. I can (technically) start coding in Language X and ultimately port the entire codebase to Language Y (or take bits of Language A, B, and C). It's not so much about choosing the right language as reacting to the ever-changing world in which your software is being deployed.