How do you know which girl to ask out at a bar?
There are things you can tell about a bow without shooting it. Does it appeal to your eye, is the grip comfortable in my hand, is the pull smooth?
If you look at a target and close your eyes, then draw, and then open your eyes does the arrow seem to be pointing where it needs to be? Was the draw smooth? Did it feel like it loaded up more initially, or at the end of the draw, or equally throughout? Are you fingers pinched at full draw? Can I pull the darned thing? Does it seem squirrely or stable in my hand at draw?
And then, even with an approximately spined arrow, was the release quiet? Did it seem to be relatively fast or slow? Did it feel good in my hand during and after release?
Some bows yopu can tell right away: grip too fat, too thin, too high, too low, etc. And if it plops that arrow smack in the bullseye you tell yourself "just think what it will be like when I get it tuned".
Shooting an untuned bow tells you much more about in than not shooting an untuned bow. ;-)