system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does Siri require internet access to perform a task like playing a song that's already on my phone? Also, why does it need to know my location, simply to tell me the distance between 2 cities?
gpt
Voice recognition and the associated language processing isn't something your phone and its little battery can handle very well. Instead your voice commands are sent off to a central server to be processed and the results sent back to your phone. This means Siri will require internet access to work because, despite how it seems, "Siri" isn't resident in your phone.

When asking about the distance between two cities you are likely invoking a map program which is anticipating providing information useful to you in particular. Knowing your location will allow it to tell how far away you are from cities, plan routes, and even disambiguate between locations (if you are in Texas and type "Paris" you probably mean Paris, TX and not France).

Now you might not actually be wanting any of that, you might just want to know the distance between two cities and your location is irrelevant. But the app can't know that, it wants to access data it was programmed to anticipate is useful. Also it needs to ask at launch because you don't want that question popping up suddenly in the middle of using the app when it becomes absolutely necessary.