if it works 90% of the time that means it fails 10% of the time, to get to 1% failure rate is a 10x improvement and from 1% failure rate to a 0.1% failure rate

if it works 90% of the time that means it fails 10% of the time, to get to 1% failure rate is a 10x improvement and from 1% failure rate to a 0.1% failure rate is also a 10x improvement First time being hearing it be called "march of nines", did Tesla make the term, I thought it was an Amazon thing