Getting to 80%

I recently worked my way through a fantastic podcast between Arthur Brooks, a professor at the Harvard Business School, and Tim Ferriss. Brooks studies the idea of happiness and has written many books on the subject.

While there were a number of interesting things discussed, there’s one part of the conversation I can’t stop thinking about. Specifically, Brooks was discussing Marine leadership principles and mentioned that the best leaders making important decisions are trained to reach around 80% certainty before moving forward.

He called it the “80% rule.” And his point was straightforward: 100% certainty is a fantasy. The leaders who actually get things done have learned to recognize when they have enough to act, and they do.

I’ve been thinking about this idea ever since. Because here’s the thing…I’ve seen this play out in lean and continuous improvement work more times than I can count.

The Trap Nobody Likes to Admit

We talk a lot in the lean world about being data-driven. Go to gemba, observe, and deeply understand the current condition. All of that is obviously right and good. But somewhere along the way, for some (many?) people and organizations, “data-driven” becomes an excuse for inaction.

As an example. Back in my corporate days, I remember a team that had been studying the same current state value stream map for weeks. For whatever reason, they wanted one more round of data collection before taking any action. And while I don’t pretend to know exactly what was going on, it seemed to me they were hesitant to move forward due to uncertainty.

I’m not throwing stones here. I’ve done it myself. There’s a comfort in analysis. As long as you’re still studying the problem, you haven’t had to commit to a potential countermeasure yet.

Brooks & Bezos Align

Here’s the thing about the 80% rule: it’s not unique to Marine Corps leadership or Harvard professors. Jeff Bezos, from Amazon, made the same argument in his 2016 shareholder letter, suggesting that most decisions should be made with around 70% of the information you wish you had. His reasoning? If you wait for 90% or higher, you’re almost certainly moving too slowly.

The analytical black belt is now saying…ok, which is it, eighty percent or ninety percent? The specific number isn’t really the point. The point is that there’s a threshold beyond which more information doesn’t meaningfully reduce your risk…it just delays your action.

Enter Scientific Thinking

The great news for us CI folks is we can be quite comfortable once we arrive at our so-called threshold of knowledge since the discipline of Scientific Thinking, aka Toyota Kata, provides a beautiful framework to experiment and learn our way through the unknown.

Additionally, the PDCA framework is another way navigate this situation. The “Do” step exists precisely because deep learning comes from taking action, checking, and adjusting based on what we learn. You can plan all day. You can map, analyze, hypothesize, and build a beautiful A3. But until you run the experiment, you haven’t actually learned much at all.

This is also, by the way, what genchi genbutsu really means at its deepest level. Go see for yourself. Not because the data will be perfect when you get there…but because being there, in the actual process, with real people, watching real work, gives you insight that no spreadsheet or Zoom call ever will.

The Deeper Thing Brooks Is Getting At

What made Brooks’ point really land for me was when he extended the 80% idea beyond business decisions. He talked about it in the context of life decisions, too… marriage, faith, direction. He believes, and I agree, that the people who keep seeking perfect certainty before they commit often end up stuck in perpetual seeking. They never quite arrive at presence.

There’s something in that for lean practitioners, I think. Some organizations have been “starting their lean journey” for a decade. Always learning. Always preparing. Always getting ready to really start. There’s no shortage of knowledge at this point…there’s a shortage of action.

The organizations I’ve watched do lean really well; the ones who actually transform their cultures and their results aren’t the ones who waited until they had the perfect roadmap. They got to 80%… and they moved.

What About You?

So, let me ask you, what decision are you sitting on right now?

What improvement or situation (professional or personal) are you studying and thinking about instead of taking action and testing? What change are you waiting to make until you have just a little more data, a little more buy-in, a little more certainty?

If you’re honest with yourself, are you at 50%… or are you already at 80, quietly pretending you’re at 50 because moving is scarier than studying?

Get to 80%. Then go. The other 20% is waiting to be discovered at the gemba.

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