Noah Goldstein, Robert Cialdini and Vladas Griskevicius once rewrote the little card on a hotel towel rack.
The hotel's usual card said: "HELP SAVE THE ENVIRONMENT. You can show your respect for nature and help save the environment by reusing your towels during your stay."
Their version told guests that almost 75% of guests who are asked do reuse their towels, and invited them to join in.
At a midsized chain hotel in the Southwest, the save-the-planet card got 35.1% of guests to reuse a towel. The "your fellow guests do this" card got 44.1%.
In a second round they got more specific: 75% of the guests who stayed in this room reused their towels. That card hit 49.3%, against 37.2% for the standard one. That was one hotel. Later studies in other hotels found smaller effects, so test it on your own customers.
I've hung up a lot of towels in hotel bathrooms. I never once wondered who wrote that card.
Nobody touched the towels or the price. The card changed who the guest pictured doing it.
Your website asks customers to call or book. When did it last show them someone like them who already did?
Tell me in the comments which card would have worked on you.