That Moment Changed Everything: What's the Catch With S3's "11 Nines" Durability Claim?

https://www.sierrabookmarking.win/master-storage-scaling-without-vendor-lock-in-what-you-ll-achieve-in-30-days

Which questions about S3 durability will I answer and why do they matter? When Amazon S3 advertises "11 nines" durability - 99.999999999% - it sounds like an absolute safety net