How often will 98% correct data actually be worse? How often will it be better? 98% might well be disastrous, but I've seen enough awful quality human-produced

How often will 98% correct data actually be worse? How often will it be better? 98% might well be disastrous, but I've seen enough awful quality human-produced data that without some benchmarks I'm not confident we know whether this would be better or worse.