"that every unintended discharge was due to user error" -- Sig is doing a fantastic job of making it clear that that's false (as you say).

The real statement is "every unintended discharge on a known-safe gun is due to user error." I would believe that all unintended discharges on, say, a Glock 17 are user error. I no longer can believe that of Sigs.

And it's like brakes on a car. If it fails for even one person one time and causes one accident, that's too much. The stakes are way too high when you're dealing with something that can take lives if it malfunctions.

I’d wager that poorly maintained brakes fail and lead to a collision many hundreds of times per year. I think “unmodified and properly maintained”, neither firing mechanisms nor brakes should fail (and I think that’s what’s in question here).