What Is the Pygmalion Effect or Rosenthal’s Theory and Golem: Definition & Real-World Examples!

Main ideas and lessons (Pygmalion / Rosenthal Effect)

• The Pygmalion effect (also called Rosenthal’s theory) is a leadership phenomenon where expectations influence outcomes.
• While expectations begin as beliefs held by leaders, they can become self-fulfilling prophecies through how people are managed and treated.
• The video notes that the effect was first studied in schools, but it applies broadly to other contexts such as organizations and teams.

Example used: “Army experiment” (leadership expectation → performance)

Setup

• A 15-week army training course is described.
• 105 soldiers are assigned to four instructors.
• Before the course, each instructor is given a message identifying certain trainees as having been evaluated using:
  • Psychological test results
  • Grades from previous courses
  • Ratings by previous commanders
• Instructors are told soldiers’ expected “command potential” in three categories:
  • High command potential (supposedly great performers)
  • Average command potential
  • Unknown / no data available
• Key detail: the classification is described as completely random—meaning “high potential” soldiers might actually be worst performers, and vice versa.
• Instructors are instructed to learn names and scores by heart before the soldiers arrive.

Intervention (what changes)

• Once instructors believe some soldiers have higher potential, they manage them differently.
• This includes raising expectations for the “high potential” group.

Results

• After the 16 weeks (the subtitle mentions 16 weeks, while the earlier description says 15-week course), soldiers are tested.
• Performance outcomes follow the instructor expectations:
  • High command potential group significantly outperformed classmates
  • Average command potential group scored the lowest
  • Unknown potential group ended up in the middle
• The reported gap between the top and bottom groups is about 15%.

Core mechanism (how the effect works)

• Belief → leadership behavior change → changed treatment/management → altered performance
• The video summarizes it as:
  • When leaders expect greatness, they act in ways that help performance happen
  • When leaders expect low performance, they create a negative spiral that suppresses performance
• People often respond strongly to positive attention and confidence from leaders.

Practical takeaway: what leaders should do

• Be careful with how you label or categorize team members (e.g., “Maria is a high performer; Joe is average…”).
• Such labels can become self-fulfilling prophecies:
  • High-labeled people may succeed partly because they receive the leadership, confidence, and opportunity they were expected to receive.
  • Average/low-labeled people may underperform because they receive less encouragement and lower expectations.
• To increase team success:
  • Build a “can-do” environment
  • Expect success from every team member, not only a subset
  • Provide supportive management and confidence broadly (similar to how instructors were implicitly guided to treat “high potential” trainees)

Speakers / sources featured

• The video references two names/concepts associated with the same general phenomenon:
  • Rosenthal (Rosenthal’s theory)
  • Pygmalion effect (the related name for the same effect)
• It also references a “famous Army experiment”, without naming a specific individual researcher in the subtitles.