Committing in front of others increases the odds we'll follow through.
There's usually a big gap between deciding to do something and actually doing it. Committing to another person, or to ourselves in an explicit way, increases the odds that we'll follow through, because our desire to stay consistent with what we said kicks in.
A hotel wanted to reduce laundry water use by encouraging towel reuse. Instead of simply asking, it invited guests to sign an explicit commitment in front of the receptionist, in exchange for a pin that read "Friend of the Earth." The strategy increased by 25% the likelihood that guests would hang up at least one towel to reuse it. The platform stickK uses the same principle. People set a goal, sign a commitment contract, and can put money on the line that they lose if they don't follow through.
Keeping our word in front of others, or in front of a commitment we put in writing, activates our desire to stay consistent with what we already said we'd do.
Source: Baca-Motes, K., Brown, A., Gneezy, A., Keenan, E. & Nelson, L. (2012). Commitment and Behavior Change: Evidence From the Field. Journal of Consumer Research, 39(5), 1070-1084.
A public, specific commitment ("I commit to saving X this month") works much better than a vague intention ("I want to save more"). Health, financial education, or sustainability programs in Latin America can build on this without needing more budget.
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