Her knowledge: the familiarity with the forest that her childhood at Panguana had given her. The specific instruction from her father to follow water downstream. The knowledge of how to treat the wound in her arm. The familiarity with which plants not to eat, which animals to avoid provoking, how to read the sounds of the forest. This knowledge was real and specific and demonstrably useful, and without it the eleven days would have been qualitatively different.
Her decisions: to keep moving, to follow the water, to not eat the unknown fruit, to treat the wound, to wait in the camp after she had arrived. Each decision was reasonable given her knowledge and situation, and each decision, in retrospect, was correct. That does not mean they were the only possible decisions, or that any other person in the same situation would have made the same ones.
And luck: the undeniable element that is hardest to hold alongside the more analyzable factors. The specific location in the debris field where she landed. The camp existing where it did. The lumberjacks returning when they did. The search not finding her — which is to say, the search aircraft flying over her position without spotting her — allowed her to walk out rather than being airlifted before she needed to be. If the search had spotted her on day two, injured and barely ambulatory, the outcome might have been different; it might also have been better. The search not finding her meant she had to find her own way out, and she did.