That's right Jack. I question myself whether i made a mistake before judging the dog. You must, unless u like wasting precious time and potential precious dogs by making the same mistakes over and over. To each its own though, some are just very hard in selecting.

I can see what you're saying but it still makes me wonder.
You can make all the wrong choices but the capability to run fast or sing good will still be there. It was not ruined but hidden.
Now if a dog stopped while he was not ready for a roll, you obviously ruined the potential to show gameness in that particular roll. But when that same dog has become fully ready, and he carries the trait; could it be you ruined more then just his potential in his first roll? He chose the easy way out once.
If you'd compare it with the running again, and one with the potential to be a champion has not qualified for the olympics because of the wrong choises he made. Then the answer would be no, he wasnt ruined. He could still achieve it when his potential is maximized.