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The Hidden Flaw With Classic Human Performance Defenses

Guest Column | Originally Published on August 3, 2022 | Published with permission

On October 30th, 1935, the US Army Air Corps flight tested a brand new bomber -- the Boeing Model 299. It was the most advanced aircraft ever designed at that time.

Major Ployer "Pete" Hill, their most respected and experienced test pilot, was in command.

But within seconds of take off, spectators on the ground watched slack-jawed as the plane fell out the sky and crashed. Major Hill and his co-pilot died of their injuries.

Before takeoff, Major Hill had forgotten to release one of the many new safety features on the plane (the "gust lock"). The Army Air Corps generals were furious. The Engineers were stunned. And Boeing nearly went out of business. The remaining test pilots realized that errors happen even to the most highly trained and experienced pilots. They took a Learning-Based Approach to that incident and came up with an ingenious solution -- the first pilot's checklist.

Results? Armed with checklists, Army Air Corp pilots flew their B-17s on more than 1.8 million miles of missions in WWII without a major preventable incident (source).


Japanese railway operators use a technique called Point and Call. Instead of just glancing at their speedometer, operators physically touch the indicated speed and call out that speed verbally, even if working alone.

Results? Errors dropped by over 80%. (Source).


In 2001, Dr. Peter Pronovost wanted to reduce medical errors in his Intensive Care Unit (ICU) at the John Hopkins Hospital. Pronovost was uniquely motivated. His own father died from a preventable medical error.

Pronovost and his colleagues worked together to gradually evolve a clever combination of Checklists and Peer Checks into his ICU’s culture.

Results? In one 18-month-long study in Michigan, they estimated that their intervention saved over 1,500 lives. (source).


Classic Defenses

For decades, these and other “Classic Individual and Team Defenses” have helped technical experts in high-hazard industries prevent countless unwanted errors.

When leaders in high-hazard industries see results like you've just seen, they often say something like this…

“We need results like that. So we’ve chosen three of these defenses and as of today, I’m mandating the use of these defenses among all our field and front-line teams. Effective immediately. We don’t need any complex, academic theory. And I don’t ever want to hear anyone use the words ‘organizational’ and ‘weakness’ in the same sentence!”

I’ve personally heard leaders make statements like this.

I respect where they are coming from. They want practical solutions to their most urgent problems. Don’t we all?

And as a former firefighter, EMT and military paratrooper, I always aim to find practical, real-world solutions for myself, my family, my friends, and my clients.

So, why not build your entire Human

Performance (HP) program solely on these classic individual and team defenses?

The answer isn't obvious. It took me over a year to see it. Like the proverbial boiling frog, or a slow-motion train wreck, the hidden flaw revealed itself slowly, only over many months in five steps.


1. Defenses

Leaders decide to make Classic Defenses the main element of their Human Performance program. They focus only on simple, observable, behavioral techniques like:

  • Communicate Before Irreversible Steps

  • 3-Way Communication

  • Checklists

2. Mandates

Leaders start mandating the use of these classic defenses. Teams now must use Peer Checks, Confirm Terminology, etc. or face sanctions for “violating policy.” Leaders often have the best intentions here. Some say,

“Well, if a little 3-Way Communication is good, then a LOT will be better. So let’s make it required. Problem Solved.”

3. Blame

After a few weeks or months, an incident happens. Someone gets injured. A vehicle crashes. A technician throws the wrong switch in an electric substation, and 3,000 homes lose power.

Many leaders ask, “Were they using all their Human Performance defenses properly?”

If employees answer, “Yes” the leader may reply with a steely glare and ask, “Well if that were true, then you wouldn’t have made an error… right?”

An honest reply might be,

“Well, like anyone, in hindsight, I suppose I could have gotten a slightly better Peer Check, or used 3-Step Communication a bit more thoroughly. So sure, I guess there is room for improvement.”

Many traditional control-based leaders don’t see an error as an opportunity for improvement. Instead they have said things like,

“We give you the training. We give you the resources. You know the defenses. It’s your responsibility to use them. Since you didn’t use them properly, you need to be held accountable. It's that simple.”

But punishing front-line workers for making errors, or for "failing to prevent" errors always triggers unintended consequences.

4. Blowback

When word gets around that leaders are “holding front-line experts accountable” for anything less than perfect use of Human Performance defenses, trust erodes fast. Support for Human Performance sometimes disappears within weeks. The result? Front-line experts who formerly supported Human Performance initiatives, now hate them. Employees who were skeptical about Human Performance, say, "I told you so" and double down on their distrust of it and similar programs.

5. Fallout

As support for Human Performance vanishes, leaders wonder,

“What happened to our program?! When we launched it a year or so ago, employees really liked it. People used the defenses. We got some great initial results. But now all enthusiasm has just disappeared. It’s like pulling teeth to get people to use defenses now. And no one seems to even want to talk about it anymore. This Human Performance stuff doesn’t work at all.”

And that's how Human Performance programs based solely on Classic Defenses, die.


The Flaw Revealed

It took over a year for this 5-step process to play out from start to finish.

I first presented it in March 2017 at the NERC Human Performance Conference.

Now, I see this slow-motion train wreck happen far more often than I want to. I've seen dozens of companies and teams fall into this trap just as they're starting to develop a Learning-Based Approach to errors, regardless of whether they call it Human Performance, HOP, Safety II, Organizational Excellence, or something else.

The greatest strength of using Classic Defenses is also its greatest weakness.

Even one motivated individual in any organization can learn a few powerful classic defenses in minutes then apply them immediately with little or no budget, policy changes, or other organizational changes. Classic defenses give each individual great power to make an immediate difference on their own.

But leaders who focus on Classic Individual & Team Defenses without exploring any advanced, organizational strategies often wind up slowly, unintentionally creating a toxic, fear-soaked culture that focuses only the actions of front-line individuals who happen to trigger the error. The systems, processes and cultures that set people up to make errors are never discussed... or improved.

That's the hidden flaw with Classic Human Performance Defenses.


Avoiding the Trap

So, how can leaders avoid this slow-motion disaster?

Some suggest that we should avoid Classic Defenses altogether -- that they’re part of an “Old” view of safety and Human Performance -- that we need to focus solely on a “New” view instead.

I disagree.


Binary distinctions like New vs. Old, or I vs. II can be helpful for parsing out key differences in complex concepts.

For example, I teach these two core approaches to errors and surprises:

But clarifying core concepts and helping people actually apply those concepts to their adaptive, complex, high-hazard workplace are two very different animals.

"OK, I get the difference between the two approaches and really like the Learning-Based Approach.
But HOW do we get there from here?
What practical steps can we take?"

To make Human Performance practical, I use a less binary, and more versatile model. It's the model that humans have used for millennia when learning most any complex, new skill.

First crawl.

Then walk.

Then run.

So how does this look when we applied to Human Performance?

  1. First crawl -- Apply Defenses -- the basic strategy

  2. Then walk -- Improve Systems – the intermediate strategy

  3. Then run -- Build Resilience -- the advanced strategy

I think of this as the "Evolutionary Path to Human Performance."

Does it work?

“Before Jake's workshop I thought, ‘Procedures will protect the employee.’ Now I’m realizing that while still important, not all incidents can be solved by procedures.”

- Deputy Division Director at a scientific research laboratoray


I'll share more about the Evolutionary Path to Human Performance in a separate article in a few weeks.

Meantime, I welcome your honest, thoughtful comments LinkedIn post or email --

You might also find my keynotes, webinars and coaching valuable.

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