What I actually tell customers who want a "zero false alarms" guarantee

A customer asked me straight out last month: "Can you guarantee zero false alarms?" I get why she asked, false alarms are annoying and they train people to stop paying attention.

Here's what I actually told her: no, and you don't want that guarantee even if I could make it. Chasing zero false positives always means quietly raising the bar for what counts as a signal, which means real problems start slipping through as false negatives instead. You don't remove the errors, you just move them somewhere more expensive to find.

What I offered instead was the confidence grading: Verified and Very Likely are the tiers where I've tuned hard against false alarms, because that's where wrong answers cost you trust fastest. Needs Review and Monitor Only are allowed to be wrong more often, because being cautious there is cheap and being wrong there is not.

The number I actually track internally is close to 1-in-6, meaning roughly one in six flags across all tiers ends up being something the owner overrides or dismisses. I stopped trying to push that toward zero a while back, once I realized the cost of chasing it was silence on the stuff that mattered.

Would like to hear how others frame this conversation, does anyone else fight the instinct to promise "no false alarms" to a customer who's asking for exactly that?