both are true depending on the circumstance. for example going vegetarian encourages restaurants to offer more vegetarian options making entry into a vegetarian

both are true depending on the circumstance. for example going vegetarian encourages restaurants to offer more vegetarian options making entry into a vegetarian diet easier for others. Riding a bicycle makes car drivers more aware of cyclists, more awareness means it's safer to bike, means more will be willing to do it regularly, and more people who will advocate for bicycle friendly communities.