Lots of studies have looked at moral behavior, but few have looked at moral motivations. In this article in Nautilus magazine, Jim Davies reports on a huge study of almost a million individuals across multiple countries that found that people report being motivated more by helping others than more self-oriented motivations like gaining reputation. This has important implications for how we try to encourage people to be good. 

https://nautil.us/people-really-want-to-be-good-1227879/