A common misconception is that F1 cars come with a perfect tuning setup and no change is necessary. However, this is but also isn't true. Sure, they're fine as a generic, generalized setup, but if you want to dial them in for a specific track, there's room for improvement. In real life, teams actually do spend a lot of time fine-tuning their car setups for just that specific race. No car on the F1 grid ever runs on a generic, default setup.
So, if we're just wanting a generalized tune to stick with everywhere we go, the stock tuning setup is fine, but if you want to dial it in for specific tracks, there's actually room for improvement, which is why real F1 teams bother doing it in the first place.