Participants were sinifcantly more likely to help a schoolgirl reach her tardet of 100 candy cars sold
When she was 2 bars awaya from her target than when she ws 32 bars away
We tend to contribute more or work harder the closer we are to the goal
See the full study here :
Cryder, C. E., Loewenstein, G., & Seltman, H. (2013). Goal gradient in helping behavior. Journal of Experimental Social Psychology, 49(6), 1078-1083, https://doi.org/10.1016/j.jesp.2013.07.003