You only need a placeholder question when your app/script/library requires WRITE ACCES

Do not create a placeholder question before you have a reasonable idea what your app/script/library is for and are able to put that in words out in the public.

Low quality and unmaintained placeholder posts will be closed and deleted by the roomba.

See My app has to be published first? But it's still under development.

In order to use the API's write access, the app's owner must have an appropriate post that is legitimately tagged with app or script.
But this is a problem for apps that are still under initial development and not ready for general use.

The placeholder tag is thus the one time we tolerate an incomplete post -- trusting that the developer will complete the post properly once the app is ready for the public.