They are useless until one day they become extremely useful. In other words most of the time there’s minimal advantages. However by following good form you will eventually come across and instance where you have to do something and instead of having to change code in tons and tons of places, places you may not event have access to such as a public API, you don’t realize the importance. Hopefully you never across the need to do this, it’s pretty rare, but when it happens I can’t tell you how valuable it is.

The benefits are all in code maintenance. Again most of the time it’s useless but when you need I can’t tell you how incredibly useful it can be. And once you come across such an instance you never again ask why or refuse to do it ;)