Suppose that you write code without tests that compile. Suppose that those parts do not have any user interface or tests. Then what you’re doing is actually pushing development cost over to other parts of the project that make use of the code. This will probably mean that any cost/time estimates concerning dependent code needs to be adjusted in order to be able to pay for the additional cost.
Do you want to send a comment or give me a hint about any issues with a blog post: Open up an issue on GitHub.
Do you want to fix an error or add a comment published on the blog? You can do a fork of this post and do a pull request on github.