The problem, I think, is that a layperson is unaccustomed to systems like computer programs and DNA where 99% precision is laughably insufficient to specify the behavior.

If you baked some cookies and you adjusted the amount of any one ingredient by 1%... I'm not sure the average American cook has the measurement equipment to notice. With a good scale you might be able to tell. Built a shed and adjusted the measurements by 1%? It's still going to stand up just fine. Wrote an email and swapped 1 in 100 words? They might not seven notice a difference.

If you took out only the 1% that was the baking soda, or the 1% that is the nails in the rafters, or finished your email with "Screw that!" yeah, that might be hugely different...but that's exactly the kind of precision edits to critical details that computer programs and DNA require to change user-visible behavior in a huge way.