Comment by rvba

It feels as if OP independently invented the concept of six sigma.

Six sigma is a bit cultish, but overall the concept is quite clear - quality.

98% in a restaurant is horrible, because restaurants usually issue more than 100 meals per day. So 2% rate would mean a problem every day.

Although usually the distribution here would be different 98 good days and 2 bad where hundreds get food posioning..