“Those who can’t do, teach.”
It’s a phrase that’s been tossed around for generations, usually as a cheap punchline aimed at educators. But not only is it inaccurate—it completely misunderstands what great teaching actually is. In reality, those who can do often teach better precisely because they’ve done the work, faced the consequences, and navigated the messiness that theory alone can’t capture.

The best teachers are not distant observers of practice. They are translators of experience.

Doing Creates Context—Teaching Requires It

Anyone can repeat definitions, frameworks, and formulas. Teaching, however, isn’t about repeating information—it’s about making information usable. People who have done the work understand the difference between what sounds good in theory and what actually works under pressure.

A marketer who has launched campaigns knows that not every A/B test produces clean results. A designer who has shipped real projects understands that constraints—budgets, deadlines, stakeholders—shape creativity as much as inspiration does. A manager who has led teams knows that motivation isn’t a slide deck; it’s human.

When these practitioners teach, they don’t just explain what to do. They explain why, when, and what happens when it goes wrong. That context is what turns knowledge into skill.

Experience Sharpens Judgment, Not Just Knowledge

One of the most valuable things a teacher can offer is judgment. Judgment doesn’t come from textbooks—it comes from repetition, mistakes, and reflection.

Those who have done the work know:

• Which shortcuts backfire
• Which best practices are situational, not universal
• Which rules are worth breaking—and which aren’t

This kind of discernment is difficult to teach without lived experience. Practitioners-turned-teachers don’t just hand students answers; they help them think through tradeoffs. They teach decision-making, not memorization.

And in fast-changing fields—marketing, technology, design, business—judgment matters more than static knowledge.

Teaching Forces Mastery at a Deeper Level

Here’s the paradox: doing makes you competent, but teaching forces you to become precise.

When you teach something, you can’t rely on instinct alone. You have to:

• Break complex processes into clear steps
• Explain not just how something works, but why it works
• Anticipate misunderstandings and objections

Many practitioners discover that they don’t truly understand their craft until they have to explain it to someone else. Teaching exposes gaps in thinking and forces clarity. That’s why people who both do and teach often operate at a higher level than those who only do.

Teaching isn’t a fallback—it’s a refinement.

Credibility Changes the Learning Environment

Students and learners can sense authenticity. When a teacher speaks from experience, it changes the dynamic in the room.

Examples feel real, not hypothetical. Stories carry consequences. Advice isn’t abstract—it’s tested.

This credibility builds trust, and trust accelerates learning. Learners are more willing to engage, ask questions, and challenge ideas when they believe the instructor has actually stood where they are standing now.

Importantly, experienced teachers don’t pretend to know everything. In fact, they’re often more honest about uncertainty. They’ve seen enough to know that nuance exists—and that humility itself is a lesson worth modeling.

The Best Teachers Build Bridges, Not Pedestals

Those who can do and teach well don’t position themselves as untouchable experts. They remember what it felt like to struggle. They know what beginners misunderstand because they once misunderstood it themselves.

That empathy matters.

Great teaching isn’t about proving intelligence; it’s about accelerating someone else’s growth. Practitioners who teach bring realism without cynicism, confidence without arrogance, and standards without gatekeeping.

They don’t just say, “Here’s how it should work.”
They say, “Here’s how it actually works—and here’s how to navigate it.”

Reframing the Saying

So maybe it’s time to retire the old phrase—or at least rewrite it.

Those who can do bring insight.
Those who can teach translate that insight into growth.
Those who do and teach well multiply their impact.

Teaching isn’t what happens when ability runs out. It’s what happens when experience becomes valuable enough to pass on.