In A Leap for Lisa, Sam told Al that leaping has nothing to do with success and Al knows that. I was thinking, because I don't remember a single leap where Sam did not succeed in his mission, except maybe one.
In The Leap Back part 2, Sam was supposed to make sure that the mission succeeded. When all was said and done, Sam didn't complete his mission. He and Al sacrifised the mission in order to save Tom. And he did not complete the mission objective which was to rescue the POW's which included Al. Therefore, although Sam saved his brothers life, he also sacrifised Maggie's and didn'tcomplete the mission.
This was possibly his first successful failure and why Sam said that success has nothing to do with leaping
In The Leap Back part 2, Sam was supposed to make sure that the mission succeeded. When all was said and done, Sam didn't complete his mission. He and Al sacrifised the mission in order to save Tom. And he did not complete the mission objective which was to rescue the POW's which included Al. Therefore, although Sam saved his brothers life, he also sacrifised Maggie's and didn'tcomplete the mission.
This was possibly his first successful failure and why Sam said that success has nothing to do with leaping