> More to the point, why do they need to be maintainable? When was the last time you maintained the strtof function in your C library?

A few years ago. https://sourceware.org/bugzilla/show_bug.cgi?id=15744

Acting like you can get anything done right in C simply because it's self-contained is proven wrong every day. It's good practice, yes, but doesn't magically (we like this word now) make us immune to error. Everything needs to be maintainable, even if it is proven to be correct, for the simple reason that we can't just replace broken pieces of code with the same simplicity we can replace a broken fridge.

Also, if there's anything we know about code, is that we are constantly trying to invent new ways to expose it to a new interface - thereby breaking it.