There are a set of rules which govern how our world works. In the physical sciences, these rules are precise and map directly from inputs to outputs. In the social sciences, these rules are approximations and produce a general mapping from inputs to outputs.
For example, force = mass * acceleration is a physical science rule, while the input of being kind to others making them more likely to like you as an output is a social science rule.
If the rules that govern a particular context are widely known, there are a lot of people who will be able to apply those rules. As a result, the returns to applying the rule will decline due to competition.
It’s the rules that aren’t widely known that produce the greatest returns for those who identify and apply them.