Stop in for a cup of coffee

I know a lot of you know a lot more about GM cars than you like to let on, so:

Why do the ends of my Monte Carlo’s front coil springs have to be visible through the first hole in the seat in the lower control arm, but either partially or non-visible through the second hole? The assembly manual says they do, and when I look for a reason why, everybody online dutifully repeats this requirement but nobody says why it’s important. I doubt they know.

There’s a good inch more seat beyond the second hole before they'd hit bottom. Mine were a royal bee-yotch to put in, and I know we were attentive to this manual requirement when we put them in, but today I was under there and looked, and they’re in the slots, but they’re all the way in. They’re visible through both holes. So why is this a problem? Once the car’s on the road, don’t they eventually rattle and shake their way down into the bottoms of the seats anyway? There’s nothing to hold them where they start out, other than tension, and I would think gravity, inertia and their own springiness would push them down into the bases of the seats sooner or later.

If this could cause them to break or something, I sure want to know, and I’ll fix ‘em. But it’s a big pain in the butt to do, so I'd like to know why before I tear into it.