In an ideal world this is true. But in reality we don't always have control over the codebase from birth until deprecation. Often, you find yourself a newcomer to code, and being able to reason your way though it can be time consuming, and scary.

I think this article's approach is a good one. Take precautions, use things like continuous builds, static analysis tools to boost your confidence, but DO make the necessary changes. Better sooner than later.

When using unfamiliar APIs under a deadline, this can happen. Especially when the documentation for those APIs is poor and you have to plod along in the dark.

Edit: Spelling