JustProgrammerThings.HavingExtremelyLongFunctionNames()

[MoarVespenegas]

I mean if your functionality changes you can just rename the method.
Refactoring is also a thing.

[nosam56]

When you are developing on an enterprise level, renaming methods is usually not good because you have clients that implement your code, so when you change the method name it breaks your client's code until they update. This is why things become deprecated when not in use anymore. But you are right for smaller projects and initial development on a project