Reasoning Has a Half-Life

Reasoning Has a Half-Life

Yesterday, a client asked whether we could reuse an analysis I'd completed about a year ago.

“Not a problem!”

I knew I still had the workbook.

I knew I still had the data.

I knew I still had the models.

I opened the file and then...

...I just stared at it.

The worksheets were there.

Everything looked familiar-ish.

The data was there.

The executive summary was there.

I could trace through all the formulas and math.

And yet I found myself thinking,

"What exactly did I do here?"

Not because the analysis was wrong.

Because I couldn't completely remember how I'd gotten there.

Why had I chosen this approach?

What assumption(s) did I make and not make?

A year earlier, those answers had been obvious.

Yesterday...

...they weren't.

That experience reminded me of something I've been learning throughout my career.

We remember conclusions much longer than we remember the reasoning that produced them.

For years, I believed the most valuable thing to preserve was the final deliverable.

The report.

The presentation.

The model.

The recommendation.

Now I'm not so sure.

Those things preserve what we concluded.

They seldom preserve why.

And the "why" is where most of the learning lives.

Every meaningful analysis is full of decisions that never appear in the final report.

Assumptions that didn't survive.

Ideas that almost worked.

Questions we abandoned.

Questions we should have asked sooner.

Moments when we realized we'd been solving the wrong problem all along.

The client sees the outcome.

But the journey quietly disappears.

For most of my career, I viewed preserving the journey as a form of accountability.

Now I think it's just as much (if not more so) about continuity.

Yesterday, the person who most needed an explanation of my reasoning...

...wasn't my client.

It was me.

That realization bothered me more than one might expect.

I hadn't forgotten statistics.

I hadn't forgotten the tools.

I hadn't forgotten how to analyze the problem.

I'd forgotten some of the context.

The tradeoffs.

The assumptions.

The seemingly insignificant moments that changed everything that came afterward.

Those moments almost never appear in the final presentation.

They're also the moments I probably learned the most from.

I've come to believe that reasoning – that is, how we came to our result and recommendation - has a half-life.

Left undocumented, it slowly decays.

Months later, the conclusion remains.

The reasoning begins to fade.

Eventually, even we struggle to explain why we once believed it was the right conclusion.

The decision survives.

The thinking doesn't.

Organizations tend to be decent at preserving outcomes.

Reports.

Dashboards.

Presentations.

Decisions.

They're much less effective at preserving the thinking behind them.

I suspect that's where much of an organization's knowledge quietly disappears.

Not when people leave.

Long before they leave.

When the reasoning behind yesterday's decisions quietly dissolves into conclusions that no longer carry their own explanation.

Good analysis isn't just about arriving at a sound conclusion.

It's about preserving enough of the journey that someone - including your future self - can understand why that conclusion made sense at the time.

Because someday...

...you'll open an old workbook with complete confidence.

And discover that the most valuable thing you lost wasn't the answer.

It was the thinking that led you there.

Reflection

A year from now, when you revisit one of today's most important decisions...

Will you remember your conclusion?

Or will you still remember the reasoning that earned it?