Knowing the way reliability engineers calculate their "analysis" I'd be very interested to go through the report they cook up for the FAA to prove the one-in-a-billion compliance! LOL!
"One-in-a-billion" seems like pretty tight reliability, but safety is paramount. Not sure how they test FoM (first of model) and how much is done by analysis. Probably not like military planes where they actually break the plane to test its limits.