You don't need a text nor caption nor audio log telling you you've completed your mission or tasks in various offline games, you should know you've completed it once you've killed your last enemy/gained last item.

There's no such thing as redundancy unless it's the same system, which in this case it doesn't pop up a display text telling you:

"1 Party member added!"

"2 Party members added!"

Then you'd have an argument.