Rosenthal and Jacobson’s (1968) classroom experiment is the most cited starting point: teachers were told that specific students were about to experience intellectual growth. Those students subsequently outperformed their peers on measured assessments. The students had been chosen at random. The only variable was the teacher’s expectation. The experiment’s replication picture is more qualified than the popular management account suggests — the original IQ effects were largely confined to the youngest children and the effect sizes were modest in subsequent meta-analyses — but the core finding has proven robust across fifty years of research in classrooms, military training, and workplace settings. Leader expectations shape follower performance. The mechanism is now understood well enough to be practically useful.

The four channels through which expectations travel

Rosenthal’s (1994) synthesis of the research programme identified four specific behavioural channels through which expectation-consistent behaviour operates: climate, input, output, and feedback. The leader who holds high expectations of a team member unconsciously provides warmer interpersonal climate, more developmental input and attention, more opportunities for performance display, and richer and more specific feedback — independently of whether that person had previously demonstrated superior performance. The leader who holds low expectations provides less of all four.

This is the practically important finding. The expectation does not produce performance through some direct cognitive transmission; it produces it through the specific behaviours that the expectation generates in the leader — behaviours that are below deliberate awareness and that cumulatively create the conditions either for development or for stagnation. The team member in a high-expectation relationship is receiving more warmth, more challenge, more visibility, and more developmental feedback than the team member in a low-expectation one. The performance difference that follows is not mysterious.

Eden’s (1990) research across multiple sectors and work groups confirmed the effect in workplace settings: supervisors who held positive expectations of team members’ performance produced measurable performance improvements; those who held negative expectations produced measurable performance declines. The Israeli Defence Forces research documented the effect with particularly clean controls, since military training performance is objectively measurable and the expectancy manipulation was rigorously implemented. The finding generalises across sectors and roles.

How the expectation changes the follower’s self-expectation

The Galatea effect — the complementary mechanism to the Pygmalion effect — establishes how the leader’s expectation produces changed performance in the follower. The four-channel behaviour that the leader’s expectation generates creates an experience of being treated as high-potential. This experience changes the follower’s own self-expectation — their belief in their own capacity to perform the relevant tasks. Bandura’s (1997) self-efficacy research provides the neuropsychological account: changed self-expectation changes the self-efficacy that predicts performance on difficult tasks. The mechanism is not social pressure; it is the genuine internalisation of the expectation that the leader’s behaviour has communicated through climate, input, output, and feedback.

The practical implication is that the leader’s expectation is already operating on their team’s self-belief through the behaviours the expectation generates — regardless of whether the leader is aware of it or has explicitly communicated anything about expectations.

The Golem effect and why negative expectations are the more consequential problem

The Golem effect — the reverse mechanism — may be more practically consequential for entrepreneurial teams than the Pygmalion effect. When a leader has concluded that a team member is underperforming, they unconsciously reduce their climate warmth, their developmental investment, their assignment of meaningful performance opportunities, and the specificity of their feedback to that person. This withdrawal of the four channels produces the underperformance that confirms the original expectation.

Babad, Inbar and Rosenthal’s (1982) research documented this mechanism with the same rigour as the original Pygmalion finding. The leader who concludes a team member is a poor fit may be actively creating the poor fit through the withdrawal of the conditions that would allow the person to develop and perform. The performance management decision that follows — the conclusion that the person is not capable — may be attributing to the person a failure that the Golem-effect withdrawal of development produced.

The limitations the research requires acknowledging

The Pygmalion effect is real and operationally important, but the research imposes honest limitations. The effect does not generalise equally across all contexts: it is weaker in established work groups where team members have track records that resist expectation revision, and the evidence base is thinner for experienced senior hires than for junior team members in early stages of role development. Most significantly, the subconscious nature of the mechanism means that telling leaders to hold high expectations is not a reliable intervention if they do not genuinely hold them — the four-channel behaviour follows from genuine expectation, not from declared intention. The leader who commits to treating a team member as high-potential while privately doubting it will not reliably produce the Pygmalion effect.

Books worth reading on this

Multipliers by Liz Wiseman. Wiseman’s research on leaders who amplify the intelligence of their teams versus those who diminish it operationalises the Pygmalion and Golem mechanisms in practical leadership terms. Her specific account of the behaviours that distinguish leaders who elicit high performance from those who suppress it is the most directly applicable popular treatment of the four-channel model — and her research on the Diminisher pattern maps precisely onto the Golem effect’s withdrawal of climate, input, output, and feedback. Developing the Leader Within You by John Maxwell. Maxwell’s account of how leaders’ beliefs about their people shape the culture and performance of their organisations is the most widely read popular treatment of the expectation-to-performance mechanism. His specific account of how leaders who invest in the potential of their people produce fundamentally different organisational outcomes from those who invest only in their current performance is the applied version of the Eden workplace Pygmalion research.

If the dynamics described here are significantly affecting your wellbeing, speaking with a psychologist is the right next step. UK: Samaritans (116 123, free, 24/7). Mind (0300 123 3393). BACP: bacp.co.uk/search/Therapists. Crisis Text Line — text HOME to 741741 (US, UK, Canada, Ireland). International: internationaltherapistdirectory.com.

This article is for educational and informational purposes only. Sources: Rosenthal, R. & Jacobson, L. (1968), Pygmalion in the Classroom, Holt, Rinehart & Winston. Raudenbush, S.W. (1984), Magnitude of Teacher Expectancy Effects on Pupil IQ as a Function of the Credibility of Expectancy Induction, Journal of Educational Psychology, 76(1), 85–97. Rosenthal, R. (1994), Interpersonal Expectancy Effects: A 30-Year Perspective, Current Directions in Psychological Science, 3(6), 176–179. Eden, D. (1990), Pygmalion in Management, Lexington Books. Babad, E.Y., Inbar, J. & Rosenthal, R. (1982), Pygmalion, Galatea, and the Golem: Investigations of Biased and Unbiased Teachers, Journal of Educational Psychology, 74(4), 459–474. Bandura, A. (1997), Self-Efficacy: The Exercise of Control, W.H. Freeman. Rusbult, C.E., Finkel, E.J. & Kumashiro, M. (2009), The Michelangelo Phenomenon, Current Directions in Psychological Science, 18(6), 305–309. Dobelli, R. (2017), The Art of the Good Life, Sceptre. Wiseman, L. (2010), Multipliers, HarperBusiness. Maxwell, J.C. (1993), Developing the Leader Within You, Thomas Nelson.