What this analysis tells me is that if you take people who love something (after all, the students who took part in this experiment signed up for an experiment to build Legos) and you place them in meaningful working conditions, the joy they derive from the activity is going to be a major driver in dictating their level of effort. However, if you take the same people with the same initial passion and desire and place them in meaningless working conditions, you can very easily kill any internal joy they might derive from the activity.
On the other hand, if you want to motivate people working with you and for you, it would be useful to pay attention to them, their effort, and the fruits of their labor.
If companies really want their workers to produce, they should try to impart a sense of meaning—not just through vision statements but by allowing employees to feel a sense of completion and ensuring that a job well done is acknowledged.
These results imply that investing more effort does, indeed, increase our affection, but only when the effort leads to completion. When the effort is unfruitful, affection for one’s work plummets.