Comment 3 for bug 1394669

So, just to clarify, there are two different dialogs:

1) "Set default sim card for calls if none is defined yet" which is displayed during the app startup. If you tap "No", it will never be displayed again. If you tap "Later" 3 times it will also not be displayed again.
2) "Choose which sim to use for a given call", which is triggered every time the user tries to make a call and the option in system-settings is "Always ask".

Changing the option to "Always ask" in system settings tells the phone "I want to be asked which sim card to use every time I make a call", and not "Open the dialog to select the default sim card every time I open dialer-app". In other words, system-settings option only changes the behavior of dialog number 2. The same applies to messaging-app.

The bug report is about controlling the behavior of dialog 1.