Focus the change on the situation, not people

In the book Switch: How to Change Things When Change Is Hard by Chip Heath & Dan Heath, the authors described the results of a study to answer the question: Would people with bigger popcorn buckets eat more at the movie cinema?

As part of the study, it was carefully engineered to serve the popcorn five days stale.  Some people received medium sized buckets and others got a large bucket.  The results were stunning:

People with the large buckets ate 53 percent more popcorn than people with the medium size. That’s the equivalent of 173 more calories and approximately 21 extra hand-dips into the bucket.

The book further states that other popcorn studies were always the same:

It didn’t matter if our moviegoers were in Pennsylvania, Illinois, or Iowa, and it didn’t matter what kind of movie was showing; all of our popcorn studies led to the same conclusion. People eat more when you give them a bigger container.”

No other theory explains the behavior. These people weren’t eating for pleasure. (The popcorn was so stale it squeaked!) They weren’t driven by a desire to finish their portion. (Both buckets were too big to finish.) It didn’t matter whether they were hungry or full. The equation is unyielding: Bigger container = more eating.

Recently in To Change Culture, Change the System David Joyce says:

Deming learned it’s not a problem of the people it’s a problem of the system that people work within. He found that if you want to change behaviour, then you need to change the system, and change management thinking that creates it. Doing so, culture change is then free.

To change someone’s behaviour, you’ve got to change that person’s situation.