The big issue here is that Siri says “I’ll send your message.” Was it sent? Or is it stuck somewhere? Will it be sent immediately or 10 minutes from now?
The interface doesn’t reflect that the message was ever sent.
Apple does things like this because they want Siri to appear conversational. In some cases, it responds “Done.” to the same command. If you were to ask a friend 10 times to do something, the response each time might vary: “Yup” “Got it” “Done” “I’ll do it.” etc. That makes sense when you’re talking to a human. Not so much when you want predictability from your phone.
From redesign’s Victor Marks:
Bonus points for this comment:
Apple clears the message information off the screen and wastes a lot of real estate.