The point of both parkour & climbing is simply “do not fall”. If the challenge is to conquer an obstacle, to ‘send’ it, then falling is the losing condition. Climbers and traceurs alike train hard to not fall, but to believe you never will is folly. Rather, we need to train to fall.
Both of these sports are dangerous, and as such, falls can result in serious injuries. Climbers (generally) take a lot of precautions; using ropes and harnesses and helmets, learning advanced roping techniques, developing safety and rescue procedures.
Traceurs tell you to land on the balls of your feet and bend at the knees.
While climbing is more about trying to safely control a situation with gear, parkour is about creating a safe environment through training and awareness. Knowing how your body moves, how you can move it, is the foundation of safety in parkour.
This is why there is such a focus on “perfect form” in parkour. Form is literally the difference between a broken ankle and walking away. Form is your safety mechanism.
The problem here is with redundancy; the second anchor so to speak. Form can never be perfect, and often pushing yourself close to your limits is the only way to develop. So we challenge the extent of our form in order to improve it. And if form fails, what is left to save us?
We cannot fly, but we can always fall with style.