it held among participants with strong but not weak commitment to the identity goal (Study 3).
That suggests to me that "strong commitment to the identity goal" is the sign of extrinsic motivation (I don't actually want to become a lawyer, but I say I do), whereas "weak commitment to the identity goal" is the sign of intrinsic motivation (I actually enjoy the law, and so should probably become a lawyer). The first group is doing it mostly for signalling- and so once they have confirmation that their signals have been received, they feel less need to send them.
Popularisation, extremely short
Original Article [pdf]
When intentions go public: does social reality widen the intention-behavior gap?
Source
New York University, Psychology Department, New York, NY 10003, USA. peter.gollwitzer@nyu.edu
Abstract
Based on Lewinian goal theory in general and self-completion theory in particular, four experiments examined the implications of other people taking notice of one's identity-related behavioral intentions (e.g., the intention to read law periodicals regularly to reach the identity goal of becoming a lawyer). Identity-related behavioral intentions that had been noticed by other people were translated into action less intensively than those that had been ignored (Studies 1-3). This effect was evident in the field (persistent striving over 1 week's time; Study 1) and in the laboratory (jumping on opportunities to act; Studies 2 and 3), and it held among participants with strong but not weak commitment to the identity goal (Study 3). Study 4 showed, in addition, that when other people take notice of an individual's identity-related behavioral intention, this gives the individual a premature sense of possessing the aspired-to identity.
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