Your Best Salesperson Will Probably Make Your Worst Manager. The Data Explains Why.

Here's how many organizations decide who becomes a leader:

Step 1: Find the person who is very good at their current job.Step 2: Promote them into a completely different job.Step 3: Act surprised when they struggle.

It feels like the fair, obvious choice.

Reward the top performer with the bigger role.

But there is a quiet flaw in that logic:

Being excellent at a job and being able to lead the people who do that job are two very different things.

Research around the Peter Principle has highlighted this problem for decades. In some studies, teams led by promoted top performers actually performed worse than teams led by former average performers.

That is how a company can turn:

Its best salesperson into an exhausted sales manager.

Its best engineer into a reluctant people manager.

Its best branch performer into a regional leader who spends the day asking why everyone's numbers are red.

The person wasn't necessarily the wrong person.

They were simply excellent at a different job.

Quick Answer

Organizations routinely promote high performers into leadership because strong performance feels like the safest signal of future success.

But the skills that make someone an excellent individual contributor are not necessarily the skills required to lead.

Leadership requires capabilities such as:

• Coaching and developing others

• Delegating effectively

• Influencing without authority

• Making decisions with incomplete information

• Managing competing priorities

• Handling stakeholder pressure

• Balancing people, performance and business outcomes

That creates an uncomfortable question:

Does success in the current role actually tell us whether someone is ready for the next one?

Not reliably.

Past performance tells you what someone has already demonstrated in a familiar context.

Leadership readiness asks what they can do when the context changes.

The better question isn't "Who performed best?"

It's "Who is ready for what comes next?"

Leadership Is a Different Game

The core mistake is treating leadership as individual performance with a larger chair.

It isn't.

Leadership is a different game.

Different rules.Different pressures.Different consequences.Different scoreboard.

A salesperson wins by closing.

A sales manager wins by making twelve other people better at closing.

An engineer may succeed because they can solve difficult technical problems themselves.

A manager succeeds because they can help an entire team solve problems, make decisions and work together.

A branch performer may consistently deliver outstanding numbers.

A regional leader has to get results through multiple branches, managers, stakeholders and competing priorities.

The job changed. So the definition of success changed.

You're Promoting on the Left. The Job Is on the Right.

Current Role Success

• Clear targets

• Known processes

• Direct control

• Familiar problems

• Individual accountability

• One primary scoreboard

  
  

Next-Level Leadership

• Ambiguous goals

• Competing priorities

• Multiple stakeholders

• Incomplete information

• Limited direct control

• Responsibility for other people's performance

The person may have demonstrated everything required on the left.

But the promotion asks them to perform on the right.

That's the gap organizations often fail to test.

Why Past Performance Can Mislead

Past performance isn't useless.

It tells you what someone has already demonstrated in a known environment.

But leadership potential is a different question:

What can this person do when the environment becomes unfamiliar, ambiguous and more complex?

That's where past performance can quietly become a misleading signal.

Someone can be:

Excellent when the goal is clearbut struggle when the goal is contested.

Excellent when they control the workbut struggle when they must influence people they don't control.

Excellent when the problem is technicalbut become overwhelmed when it becomes political, emotional, commercial and operational at the same time.

Excellent at executionbut struggle with judgement.

Confident in their expertisebut not necessarily effective at leading others.

Promotion based purely on past performance can therefore confuse:

Reliability with readiness.

Expertise with judgement.

Confidence with leadership.

And that distinction matters because a promotion is not simply a reward.

It changes the job.

What Actually Predicts Leadership Readiness?

Evidence of handling complexity.

If past performance cannot reliably tell us whether someone will lead well, what should we look at?

The behaviour required in the next role.

Instead of trying to infer leadership ability from someone's current performance, put them into a safe but serious version of the challenges they will actually face.

Give them:

• Competing stakeholders

• Incomplete information

• Conflicting priorities

• Difficult trade-offs

• Pressure from multiple directions

• Decisions with no perfect answer

Then observe what they actually do.

Do they make the call?

Can they influence without authority?

Can they prioritise when everything feels urgent?

Can they protect ethics under pressure?

Can they balance people, performance and business outcomes?

Can they make a decision when they only have 60% of the information?

These are very different questions from:

"Were they the best salesperson on the team?"

From Performance to Readiness

This is where a leadership simulation becomes useful.

A leadership simulation doesn't ask someone to simply talk about leadership.

It creates a realistic situation in which they actually have to lead.

They have to make the decision.

They have to manage the trade-off.

They have to influence someone.

They have to decide what matters most.

They have to deal with incomplete information.

They have to live with the consequences of the choice.

That gives an organization something that a promotion based purely on historical performance cannot:

evidence of how the person handles the demands of the next role.

How R2R Scale Approaches Leadership Readiness

The thinking behind R2R Scale is straightforward.

01 — Define the leadership level

Start with the role.

What does success actually look like at the next level?

What decisions will this leader have to make?

What complexity will they inherit?

02 — Identify the capabilities required

Translate the role into the behaviours and capabilities that matter.

For example:

• Judgement

• Influence

• Prioritisation

• Decision-making

• Stakeholder management

• Coaching

• Commercial thinking

• Ethical decision-making

  
  

03 — Simulate the reality

Create realistic situations that reflect the challenges of the role.

Not generic leadership questions.

Not theoretical scenarios.

Situations that require the person to actually make decisions.

04 — Observe the evidence

Look at how the person responds.

How do they prioritise?

How do they make decisions?

How do they handle pressure?

How do they influence others?

What do they do when there isn't an obvious right answer?

05 — Make a better promotion decision

The question changes from:

"Who was the strongest performer in the current role?"

to:

"Who has demonstrated readiness for the next one?"

That is a much stronger basis for a high-stakes promotion decision.

The Real Difference Between Performance and Readiness

A strong performer excels at delivering their own work in a familiar environment.

A leader has to get results through other people, often while dealing with ambiguity, competing priorities, stakeholder pressure and incomplete information.

That's why:

Performance proves what someone has done.

Readiness asks what they can do next.

The two can overlap.

But they are not the same thing.

And organizations that treat them as the same thing can end up promoting people into roles they were never actually tested for.

The Big Idea

Your best performer isn't necessarily your next best leader.

The question isn't whether someone deserves a promotion.

The question is whether the evidence supports their readiness for the new role.

Because leadership isn't about doing more of what made someone successful before.

It's about succeeding at a fundamentally different job.

Frequently Asked Questions

Why do good employees fail after being promoted?

The capabilities that made someone successful as an individual contributor can be different from the capabilities required to lead.

Technical expertise, personal drive and strong execution can make someone excellent at their current role. Leadership adds coaching, delegation, influence, judgement and the ability to make decisions in ambiguous situations.

When promotion is based primarily on past performance rather than readiness for the new role, even highly capable performers can struggle.

What is the Peter Principle?

The Peter Principle, coined by Dr. Laurence J. Peter in 1969, describes the tendency for people in hierarchical organizations to be promoted based on success in their current role until they reach a role where their demonstrated capabilities no longer match the demands of the job.

The central problem is simple:

The promotion rewards what someone has already proven rather than testing what the new role requires.

Does high performance predict leadership ability?

Not reliably.

Performance demonstrates what someone can do in a particular role and environment.

Leadership requires additional capabilities, including handling ambiguity, complexity, people, stakeholders and competing priorities.

Research has found that job performance can have limited bearing on leadership effectiveness, and some studies have found teams led by promoted top performers performing worse than teams led by former average performers.

The point isn't that top performers make bad leaders.

It's that top performance alone isn't enough evidence of leadership readiness.

How can companies avoid promoting the wrong people?

By assessing readiness for the next role, rather than relying only on performance in the current one.

That means identifying what the next role actually demands and then observing whether the person can handle those demands.

A realistic leadership simulation can provide a safe environment to test decision-making, influence, prioritisation, stakeholder management and judgement before making a high-stakes promotion decision.

What's the difference between being a strong performer and being ready to lead?

A strong performer excels at executing their own work.

A leader must get results through other people.

That means dealing with situations where:

• The answer isn't obvious

• The information is incomplete

• Stakeholders disagree

• Priorities compete

• The person doesn't have direct authority

• Every option has a downside

Being good at today's job is evidence of performance.

Handling tomorrow's challenges is evidence of readiness.

Watch the full breakdown on YouTube. 

The R2R Lead explainer shows why promotion by past performance backfires — and what leadership simulations reveal instead. 

[LINK: R2R Lead explainer video] 

Curious how this applies to your leaders? 

R2R Scale is how we design leadership simulations that test whether someone can handle the next level — before you promote them. We walk organizations through how it maps to their roles.  Let's talk. 

[LINK: Get in touch]