Before repeating percentages I've heard and read, I'll give an example of how the context of a measure matters. B's tests are regression tests, designed to be repeatable. We don't know if they're automated or not - that's not relevant to this example. One-shot tests are intended to be run exactly once. Nothing is done that would enable anyone to run them again.
Regression tests find bugs in two ways.
They can find bugs the first time they're run, and they can find bugs when they're re-executed. One-shot tests have only one chance to find a bug. A has a pretty impressive set of regression tests. In their case, rerunning tests isn't finding as many bugs as running tests for the first time. They might have found 210 bugs instead of the 100 they did find.