Satnavs are actually too polite - explicitly telling the driver that they went wrong (sans insults of course!) is useful information that could avoid a lot of confusion.
I imagine the reason that this is not done is the same reason as lots of sound engineering is compromised - marketing dweebs.
I don't much care for a machine saying "please" and "thank you". If it's not going to insult you, it could at least say "yes, your worship" or "by your command".
I imagine the reason that this is not done is the same reason as lots of sound engineering is compromised - marketing dweebs.