Think of a digital identity as a key. It’s not good enough to standardize a key alone – locks must be standardized, too, so that the key works correctly within it. To carry on the analogy, a screwdriver or a different key, shouldn’t open the lock. It is essential to know only the right key will open the lock. The QPL tests locks and keys to make sure they work together properly to achieve security, interoperability, and convenience.