But the underlying metric that actually matters, the number of users converted, did actually improve by 21.1%. I think it's just a matter of using confusing la

But the underlying metric that actually matters, the number of users converted, did actually improve by 21.1%. I think it's just a matter of using confusing labels to refer to the percentages/improvements. In other words, you don't really care about the second derivative (the rate at which the conversion rate) is improving as much as you care about the initial rate.