We want to be in consensus with others. People are likely to follow the lead of multiple, comparable others.
Science
A Field Experiment about Household Energy Conservation: Random homes in San Diego had put a sign on their doors with 4 different reasons to safe Energy Consumption. The Messages on the different signs were as follows: 1 Do this to safe the environment, 2 Do this to be a socially responsible citizen, to benefit the society 3 Do this for your own economic self interest, to safe money 4 The majority of your neighbors are undertaking energy conserving actions. Which Reason led to significant reduce in Energy consumption? Only Sign which made a significant difference in the Energy consumption was the fourth one: what your neighbors are doing! Results of the Control Group showed: Simply urging people to do something was the same as doing nothing.
Key takeaways
References
Cialdini, R. B., & Martin, S. (2012). Science Of Persuasion. https://www.youtube.com/watch?v=cFdCzN7RYbw&t=447s&ab_channel=influenceatwork