We like to imagine ourselves as perfect machines—epitomes of perception possessing amazing abilities to grasp complex patterns: analyzing, comparing, and passing judgment that holds water.
Perhaps it's a disappointment to some that in reality, we're not very good at it. In fact, we're only human.
Which is one reason why we cannot use an A/B switch box to compare audio differences in imaging and inner detail, or simple measurements that attempt to describe the complexities of what we hear.
If we're after the truth, we need to accommodate our frailties. Our senses need time to adjust to new circumstances and reset ourselves.
After, all, we're only human.