Is one in 10,000 good enough?

Great White Copy paper

According to this box of photocopy paper it is 99.99% jam-free. (No word on the peanut butter content.)

Great White Copy paper - Detail

That figure, 99.99%, means that one sheet in 10,000, or one in every two boxes, will jam. Is that a good level of quality? Would one in 300,000 be better? Would that level of failure be acceptable. Most people would say yes. One in 300,000 is pretty darn good. Not much to complain about there.

Of course, once I give you the context then the picture changes. Every year there are over 300,000 takeoffs and landing at YVR, Vancouver International Airport. So one failure there has a pretty serious impact.

And that is the critical point about any quality statistic. Without context, the statistic is pretty useless.