GOOD SETUP:
It’s cool, I can’t see where it’s going, I’ve never seen it before, it’s doing something fun while establishing something important for later.
BAD SETUP:
I’ve seen it before, I know how it works, nothing happens. A yawn.
Setup is the reader’s introduction to your ability to innovate and surprise. Spend some time on developing interesting ideas and use them to disguise what you’re setting up.