Absolutely agreed.
Every rep needs to be a perfect rep.
If it isn't, it's just burning-in imperfections.
Practice doesn't make perfect. It may increase one's capabilities, but that is not a 1:1 correlation with perfection. To achieve perfect performance, one must have strive for perfect practice.
I'm -NOT- a professional gunman, so this is even more important to me. Every time I get to handle my gun is one rep, and every rep matters.