“People choose to engage with a goal when the opportunities for goal attainment are favorable.”
“People choose to disengage from a goal when the opportunities for goal attainment are unfavorable.”
Heckhausen, Wrosch, & Schulz (2010) “A Motivational Theory of Life-Span Development”
More goes into the decision to engage a goal than just favorable opportunities. Difficulty/effort, cost of failure, tolerance of risk and delay, payoff, opportunity costs, anticipated duration or repeat of favorable opportunities, etc. – all are part of the decision to engage a goal.
Favorability and unfavorability are matters of degree. The favorability tipping point for goal engagement varies with all those other factors mentioned above. For instance, opportunities for goal attainment could be relatively poor and still trigger engagement when the cost of goal pursuit is low and the potential payoff high. Buying a lottery ticket comes to mind.
For some people, the mere possibility of achieving a goal matters more than favorable opportunities. A chance, not necessarily a good chance.* In the classic movie Dumb and Dumber, that was all Jim Carrey’s character, Lloyd Christmas, needed to keep pursuing the girl of his dreams, Mary Swanson:
Lloyd Christmas: I want to ask you a question, straight out, flat out, and I want you to give me the honest answer. What do you think the chances are of a guy like you and a girl like me ending up together?
Mary Swanson: Well Lloyd, that's difficult to say. We really don't...
Lloyd Christmas: Hit me with it! Just give it to me straight! I came a long way just to see you Mary, just... The least you can do is level with me. What are my chances?
Mary Swanson: Not good.
[the background soundtrack music suddenly stops]
Lloyd Christmas: [he gulps, his mouth twitching] You mean, not good like one out of a hundred?
Mary Swanson: I'd say more like one out of a million.
Lloyd Christmas: [long pause while he processes what he's heard] So you're telling me there's a chance. YEAH!
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* Of course, humans are subject to optimism bias, countered by self-protection and self-presentation concerns. These psychological cross-currents may lead us to feel more optimistic about achieving a goal than how we express our chances to ourselves and others.
Reference:
Heckhausen, J., Wrosch, C., & Schulz, R. (2010). A Motivational Theory of Life-Span Development. Psychological Review, 117(1), 32. http://doi.org/10.1037/a0017668