In the cases sited above it is sort of like those Dog shows in which each breed of dog is judged against a set of standards of perfection for that breed. No individual dog reaches every point (there are many) but some do more than others. So perfection while not a possibilty in most things, does give us a measure of how we do as individuals, the thing with being perfect is to focus not on reaching it, but how much improvement we see each time we engage a task.

or to quote Drummer/philosopher Neal Peart-"...the point of the journey is not to arrive"