Which is more persuasive: scaring someone or encouraging them?

Looks like there’s a persuasive edge for telling people what they stand to gain versus what they might lose:

Greater fear arousal is associated with greater engagement with persuasive messages, and negative information and events are more potent than their positive counterparts. Hence loss-framed persuasive appeals, which emphasize the undesirable outcomes of noncompliance with the communicator’s recommendations, should elicit greater message processing than do gain-framed appeals, which emphasize the desirable outcomes of compliance. But a meta-analytic review (based on 42 effect sizes, N = 6,378) finds that gain-framed messages engender slightly but significantly greater message engagement than do loss-framed messages. This effect is apparently not a result of whether the appeals refer to obtaining or averting negative (e.g., âskin cancerâ) rather than positive (e.g., âattractive skinâ) outcomes.

Source: “Do Loss-Framed Persuasive Messages Engender Greater Message Processing Than Do Gain-Framed Messages? A Meta-Analytic Review” from Communication Studies, Volume 59, Issue 1, 2008