[tdeck]

There's a running joke at Google that each internal tool has two versions: an old one that's deprecated and not maintained, and a new one that's being written and not ready. So I don't think these rewrites necessarily persist because they're being done well.

I keep seeing the same optimistic failure mode over and over again at each employer. It's just too tempting to rewrite, say, the SDK package deployment system rather than trying to understand and fix up the messy old Python that some past engineers left behind. And it'll only take three or four months! A year later the messy old Python with unfixed buts is still the only option because the rewrite isn't ready, and the rewrite consumed all the resources that would've been used to fix bugs.