Economists believe labour supply and demand is governed almost completely by wages. But humans are not as rational as they are assumed to be, argues Ariely. Job satisfaction and motivation play big roles in how much labour wage-earners are willing to supply.
Ariely cites experiments with animals that have shown that a number of species prefer to work for their food than receive it with no effort. Ariely designed a few experiments to show that humans have a need for their work to have greater meaning. Work that is acknowledged (as opposed to ignored, or in some cases shredded) results in labourers actually having enjoyed their work more. Such labourers were willing to do more for less, suggesting that productivity is enhanced significantly by non-monetary factors.
The rational worker does his job without worrying about whether his work has "meaning". But the real-life worker gets a great deal of motivation from even a simple acknowledgement. Employers take note!