Mayo's motivation theory and the Hawthorne studies explained

Between 1924 and 1932, researchers ran a series of experiments at the Western Electric Hawthorne Works near Chicago. They set out to answer a narrow question — how does lighting affect productivity? — and ended up founding the human relations school of management. Elton Mayo, an Australian psychologist at Harvard, became the studies' most influential interpreter.

What the studies did

The illumination experiments (1924–27). Lighting was raised for a test group and held constant for a control group. Output rose in the test group. Lighting was then lowered. Output rose again. It kept rising until the light was barely enough to see by.

The relay assembly test room (1927–32). Six women assembling telephone relays were separated into a test room. Rest breaks, hours, refreshments and pay schemes were varied. Output rose through almost every change — and stayed high when the original conditions were reinstated.

The interviewing programme. More than 20,000 employees were interviewed, initially about conditions and eventually in a much more open-ended way. This produced the finding that grievances often had little to do with their stated subject.

The bank wiring observation room (1931–32). Observers watched a group of men wiring switchboards. The group had settled on its own informal output norm — not too much, not too little — and enforced it socially, including on people who could have earned more by working faster.

What Mayo concluded

• People are not isolated economic units. They respond to the group they belong to at least as much as to the incentive in front of them.
• Informal groups set the real norms. The bank wiring room showed a work group deliberately restricting output to protect itself. Managers who ignore informal norms will be defeated by them.
• Attention matters. Being singled out, consulted and observed changed behaviour more than the physical variables the researchers were manipulating.
• Grievances are symptoms. Complaints about the canteen were often about status, fairness or supervision.

The last point produced the term now used everywhere: the Hawthorne effect — behaviour changes because people know they are being watched.

Applied in a UK workplace

Two very practical uses.

First, be sceptical of your own pilots. A ward trials a new handover process with a volunteer group; incidents fall; the process is rolled out and the improvement evaporates. Most managers conclude the process failed. Often the pilot group improved because it was a pilot group — chosen, watched, consulted. The fix is to compare against a group that also gets attention but not the intervention, and to check whether the gain persists once the novelty ends.

Second, treat informal norms as real. A distribution team has an unwritten rule about how many drops constitute a fair day. A manager who raises the target without addressing the norm gets quiet, collective resistance and no explanation for it. A manager who works with the informal leaders can move the norm. This is the single most useful thing Mayo offers a working manager.

Criticisms and limitations

The Hawthorne studies are among the most criticised in management research, and knowing why is precisely what earns marks at Level 5.

• Tiny samples. The most cited experiment involved five women assembling relays. No serious conclusion about human motivation can rest on that.
• No real control. Multiple variables changed at once and the control conditions were not maintained.
• Participants were replaced. Two women in the relay room were removed for being uncooperative and replaced with more willing workers — one of whom became the group's informal pace-setter. Output rising after that is not a mystery.
• Re-analyses disagree. Later statistical re-examinations of the original data (notably by Franke and Kaul, and by Jones) found that pay incentives, managerial discipline and the Depression-era fear of losing your job accounted for the productivity changes at least as well as social factors.
• Researcher bias. Mayo had a thesis about industrial society before the data arrived, and critics — most sharply the sociologist Alex Carey — argued the evidence was fitted to it.
• It can be paternalistic. The human relations school has been read as a way of raising output by managing sentiment, while leaving pay, power and union recognition untouched.
• "The Hawthorne effect" may be overstated. Systematic reviews have found the effect is real but smaller and less consistent than the phrase implies.

The honest position: the findings are shaky, the insight is sound, and the method is a cautionary tale about believing your own pilot.

How to evidence this in your ILM portfolio

Level 3 — Unit 315 Developing a high performing team for team norms and team development, Unit 303 Managing the performance of others for motivation in performance conversations, and Unit 310 Analysing data to make decisions where you are interpreting data from a trial. Suitable evidence:

• A reflective account of a change you piloted, analysing whether improvement came from the change or from the attention
• Workplace documents — the pilot data, the team development plan, the survey results
• A witness testimony on how you worked with informal team norms

Level 5 — Unit 504 Leading people and organisational culture for culture and informal norms, Unit 523 Data driven decision making where you are drawing conclusions from workplace data, and Unit 515 Leading innovation and change for change trials. At Level 5, critique the studies explicitly and show how their weaknesses affected how you designed or interpreted your own measurement.

Where to go next

• Herzberg's two-factor theory — the next step in motivation theory.
• Taylor's scientific management — the school Mayo was reacting against.
• Leadership theories: the complete guide