I'd say education. As people continue to recreate outdoors, over time they learn more about how to do so responsibly and adjust their behavior accordingly. Many people, myself included, make mistakes when new at an activity and hiking/backpacking is no different. However, by learning more about how these actions impact the natural world, I realized I was making mistakes and I adjusted my behavior. By exposing people to this information earlier on one could hopefully shorten the learning curve, and reduce damaging behavior. Really, I think it's important to meet people where they are at, and work with, not against, them.

"Not getting to the summit is not failure, it is an opportunity to go there again."
-Kilian Jornet-