Question

An economic term that describes happiness and is hard to measure in numbers is

Answer 1

The only abstract answer you pose us with is incentive, which would be most logical to use.

Answer 2

Utility.

Step-by-step explanation:

"Utility is used to model worth and value." It is a term referred to satisfaction that a customer receives by consuming goods and services. The term utility in economics was first coined by the most celebrated Swiss Mathematician Daniel Bernoulli.