The Decision Journal Advantage: Why Top Business Leaders Rely on This Secret for Smarter Decisions

Read time —
10 Minutes
Last updated
July 4, 2025

Nobody tells you this, but every business decision you make is a bet with your reputation on the line.

If you’re like most business leaders, decision fatigue is a daily reality. The pressure to deliver, the endless stream of choices, and the fear of making the wrong call can leave you mentally exhausted and second-guessing yourself.

Before you dive in, it’s worth clarifying the fundamentals—see [What is a Decision, Exactly?] for a clear breakdown.

But what if there was a practical, research-backed way to reduce that anxiety and actually improve your business decision outcomes?

That’s where a decision journal comes in.

By reflecting on decisions and capturing your thought process, you can minimise cognitive bias, learn from past business decisions, and build a culture of continuous improvement.

A decision journal isn’t just a notebook—it’s a strategic tool for any leader serious about making smarter, more confident choices.

What is a Decision Journal?

A decision journal is a structured, written tool that helps business leaders reflect on decisions, capture their thought process, and systematically learn from past business decisions.

A decision journal allows you to:

  • Record the context and details of each business decision.
  • Document the alternatives you considered—even those you quickly dismissed.
  • Capture your reasoning, assumptions, and any relevant data.
  • Note your emotional state and any external pressures at the time.
  • Predict the expected outcome of your decision.
  • Review the actual outcome later and extract lessons learned.

By consistently using a decision journal, you create a powerful resource for reviewing and improving your decision-making process. Over time, you’ll start to identify patterns, minimise cognitive bias, and develop a habit of intentional, evidence-based leadership.

For any leader serious about learning from past business decisions and making smarter calls in the future, a decision journal is an essential, research-backed tool.

Why Good Leaders Still Make Bad Decisions

Good leaders make bad decisions due to decision fatigue and being overwhelmed.

Even the most experienced leaders fall into the trap of decision fatigue and cognitive bias in business decisions.

You’re bombarded with choices all day—big and small. Eventually, your mental bandwidth gets fried, and your business decision outcomes start to suffer.

You might find yourself procrastinating, making rash decisions, or defaulting to gut instincts—classic signs that system one thinking has taken over.

I’ve been there.

As a business unit manager, I was responsible for managing service providers. One frantic peak season, after a string of customer complaints, I let my frustration take the wheel. The provider was late, unapologetic, and blamed the customer. I threatened to remove them from our network—an impulsive, emotional decision.

Looking back, it was a textbook case of decision fatigue, confirmation bias, and recency bias clouding my judgment.

If I’d been using a decision journal—recording my reasoning, reflecting on decisions, and learning from past business decisions—I might have recognised the pattern and made a better call.

How a Decision Journal Changes the Game

A decision journal brings discipline, reflection, and rationality to your business decision-making process. By making a habit of reflecting on decisions and recording your thought process, you force yourself to engage System 2 thinking—the slow, deliberate, and analytical mode that’s essential for high-stakes business decisions. This framework helps you sidestep cognitive biases and decision fatigue that creep in when you’re running on autopilot (System 1).

When you use a decision journal, you’re not just jotting down notes—you’re building a structured process for learning from past business decisions. Over time, you start to spot patterns, recognise where bias has crept in, and make smarter, more confident choices.

It’s like suddenly taking a train ride in Japan when you’ve been used to the slow, often-delayed trains in the UK. Once you experience the clarity and speed of making decisions with a decision journal, you’ll never want to go back to gut-feel and guesswork.

After a particularly tough peak season, I realised my team and I lacked structure around performance managing our service providers. That’s when I decided to create a decision journal template for managers—listing key questions, critical measures, and space for insights, context, and even my emotions at the time. I defined each decision I was considering and recorded my reasoning.

Soon, it was clear that journaling brought clarity to my thinking. I was better able to performance manage the provider, explain my choices, and reflect on decisions with intention.

After that experience, I started using a decision journal for every major business call.

Within a few months, I noticed fewer knee-jerk reactions and more clarity in my reasoning. My team’s trust improved, and our business decision outcomes became more consistent. Reflecting on decisions wasn’t just about avoiding mistakes—it became a way to lead with confidence and keep learning from past business decisions.

How to Use a Decision Journal: A Practical Guide

So you’re ready to start using a decision journal—but what does that look like in the real world of business?

Here’s how to use a decision journal to bring clarity, discipline, and insight to your toughest calls.

1. Choose Your Format

Whether you’re a pen-and-paper traditionalist or a digital note-taker, the key is consistency. Set up a dedicated notebook, spreadsheet, or digital document—whatever makes it easy to keep all your business decisions in one place.

2. Capture the Context

Every entry in your decision journal should start with the basics:

  • What’s the decision you’re facing? Not sure the decision fundamentals, here’s a full explanation.
  • What’s at stake for your team, your business, or your clients?
  • What’s the deadline or pressure point?

3. List the Alternatives

Don’t just record the path you took. Write down the options you considered—even the ones you dismissed quickly. This habit is crucial for reflecting on decisions later and learning from past business decisions.

4. Document Your Reasoning

This is the heart of how to use a decision journal. Spell out why you’re leaning in a particular direction. What data are you relying on? What assumptions are you making? Are there any cognitive biases you’re aware of (confirmation bias, recency bias, etc.)?

5. Note Your Emotions and External Factors

Business decisions aren’t made in a vacuum. Capture your emotional state, the team’s mood, and any external pressures—tight deadlines, client demands, market volatility. Over time, this will help you spot patterns and triggers.

6. Predict the Outcome

Write down what you expect to happen. Be specific. If you’re deciding on a new vendor, estimate the impact on cost, quality, or timelines. This step is essential for learning from past business decisions when you review your journal later.

7. Review and Reflect

Set a regular cadence—monthly or quarterly—to go back through your decision journal. Did things turn out as you predicted? What did you miss? Where did your reasoning hold up, and where did it fall short? This is where reflecting on decisions pays off, turning every entry into a lesson for the future.

Pro Tip:

Create a simple decision journal template for managers:

  • Date
  • Decision to be made
  • Context
  • Alternatives considered
  • Reasoning and assumptions
  • Emotions/external factors
  • Predicted outcome
  • Actual outcome (to be filled in later)
  • Lessons learned

Bottom line:

A decision journal isn’t just a record—it’s a tool for intentional leadership. By capturing your thinking, reflecting on decisions, and regularly reviewing outcomes, you’ll sharpen your judgment and keep learning from past business decisions long after the moment has passed.

The Role of Reflection in Business Decision-Making

Reflection is the difference between guessing and learning.

If you’re just making decisions and moving on, you’re missing the real value. A decision journal forces you to slow down and actually look back. You see not just what you decided, but why you made that call.

When you review your decision journal, you start spotting patterns. Maybe you notice you rush choices when deadlines are tight. Maybe you see the same bias showing up, again and again. This is how you start learning from past business decisions—not just repeating them.

If you want to understand the core principles behind every business choice, take a look at our in-depth guide: [What is a Decision, Exactly?] This resource breaks down the fundamentals that underpin every effective reflection and review.

Reflecting on decisions gives you a clear view of your thinking. You can see what worked, what didn’t, and where your judgment went off track. Over time, this habit builds confidence. You stop second-guessing yourself because you have the record to back up your choices.

Most business leaders don’t set aside time for this. They’re too busy, or they think reflection is just navel-gazing. But if you want better business decision outcomes, you need to make reflection part of your routine. That’s how you move from reacting to leading.

A decision journal isn’t just about writing things down. It’s about building a habit of reflecting on decisions, so you keep getting better—decision after decision, year after year.

The Payoff: Tangible Benefits for Leaders and Teams

The real value of a decision journal isn’t just in the act of writing—it’s in what happens next.

When I started reflecting on decisions and recording my reasoning, I saw a shift in how I led. That service provider incident was a wake-up call. I didn’t want to keep making the same mistakes or rely on gut instinct alone.

By using a decision journal, I began learning from past business decisions.

I could see where bias crept in, where my thinking was sharp, and where I needed to slow down. This habit didn’t just help me—it changed how my team operated.

I was able to explain my choices with clarity. My team saw the logic, not just the outcome. Trust grew, and so did accountability.

The impact was real. Fewer knee-jerk reactions. Better business decision outcomes.

More confidence in high-stakes moments. Reflecting on decisions became a routine, not a chore. Over time, it helped us avoid costly mistakes, spot patterns, and keep improving as a team.

A decision journal isn’t just a tool for leaders—it’s a way to build a culture where learning from past business decisions is the norm. When you make reflection part of your process, you set a higher standard for yourself and everyone around you.

Getting Started: Actionable Steps

Starting a decision journal doesn’t have to be complicated. The real value comes from making reflecting on decisions part of your routine and using those insights to keep learning from past business decisions.

If you want to know how to use a decision journal, here’s what works in the real world:

  • Pick your platform. You can go old-school with a notebook, use a spreadsheet, or try a digital solution. I’ve built a Notion decision journal template designed for business leaders—[check it out here] (add your link)—that makes the process structured and simple.
  • Capture the essentials. For each decision, record the context, what’s at stake, and the options you considered. Be honest about your reasoning and any emotions or pressures at play.
  • Write down your prediction. Note what you expect to happen. This is key for learning from past business decisions when you look back later.
  • Reflect and review. Set aside time—monthly or quarterly works for most—to revisit your entries. Look for patterns, see where bias crept in, and track how your judgment is evolving.

If you’re serious about improving your business decision outcomes, don’t wait for the perfect system. Start with what you have. The act of reflecting on decisions and building your own record is what matters most.

And if you want a head start, my Notion template is built to help you get going fast. It’s practical, focused, and designed for leaders who want to make reflection a habit—not just another box to tick.

Frequently Asked Questions

What is a decision journal, and how does it work?

A decision journal is a structured, written record where you capture the details of important decisions—such as the context, alternatives considered, your reasoning, emotions, and the expected outcome. By regularly reviewing your entries, you can spot patterns, learn from past choices, and improve your decision-making over time.

Who should use a decision journal?

Anyone who wants to make better decisions can benefit from a decision journal. While it’s especially valuable for business leaders and professionals facing high-stakes choices, it’s also useful for students, entrepreneurs, and anyone interested in personal growth and self-awarenes.

How much time does it take to maintain a decision journal?

Maintaining a decision journal doesn’t have to be time-consuming. You can start by spending just a few minutes recording each major decision. The key is consistency—regular, brief entries and periodic reviews will deliver the most value.

What should I include in my decision journal entries?

For each decision, include:

  • The situation or context
  • The decision you’re facing
  • Alternatives considered (and why you ruled them out)
  • Your reasoning and assumptions
  • Emotions or external factors at play
  • Your prediction of the outcome
  • The actual outcome (to review later)


This structure helps you analyze your thinking and learn from experience.

How can a decision journal improve my leadership or career?

A decision journal helps you minimize cognitive bias, build self-awareness, and make more intentional, evidence-based choices. Over time, this habit leads to better business outcomes, greater confidence, and a stronger ability to explain and stand by your decisions—qualities that are highly valued in leadership and professional growth.

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About
Darren Matthews
After a decade of studying decision-making, I share clear, practical advice to help business professionals make smarter choices.
Compass pointing towards the right direction.