Fundraising appeals stating "only 1% of people donate" use negative social proof, signaling that not donating is normal. A more effective strategy is using positive, localized social proof, like "thousands in your city already donate," to encourage participation by framing it as a common behavior.
Marketers often try to discourage an action by highlighting how many people are doing it (e.g., "many students binge drink"). This backfires by normalizing the undesirable behavior, making people more likely to do it. This psychological pitfall is known as negative social proof.