The Psychology Behind Why Good Employees Make Terrible Supervisors

Three weeks ago, I watched Sarah—one of our best project coordinators—reduce a 25-year veteran to tears in her first team meeting as a supervisor. The irony wasn't lost on me. Six months earlier, Sarah had been the office hero, the person everyone turned to when deadlines got tight and clients got demanding.

Now she was a walking disaster with a title.

This isn't unusual. In fact, after fifteen years of running workplace training sessions across Melbourne, Sydney, and Brisbane, I've seen this pattern repeat itself more times than I care to count. The best individual contributors often become the worst supervisors, and it's not because they're bad people.

It's because we've fundamentally misunderstood what makes someone good at supervision.

Here's what most companies get wrong: they promote based on technical competence rather than supervisory potential. Sarah was brilliant at juggling multiple projects, meeting impossible deadlines, and keeping clients happy. But none of these skills translated to managing people who weren't Sarah.

The psychology behind this failure is fascinating and depressing in equal measure.

Star employees succeed because they've mastered their own productivity systems. They know exactly how they work best, what motivates them, and how to push through obstacles. When they become supervisors, they unconsciously assume everyone else should work the same way. When team members struggle with Sarah's methods, she doesn't see it as a training opportunity—she sees it as incompetence.

I call this "competence bias." The better someone is at their job, the less they remember what it was like to struggle with it. Ask any expert to teach a beginner, and you'll watch them skip over fundamental steps that feel obvious to them but are mystifying to newcomers.

Sarah made this mistake in spades. In her first week as supervisor, she restructured the entire team's workflow to match her personal system. No consultation. No transition period. Just "this is how we're doing things now."

The veteran who ended up in tears? She'd been using a completely different organisational method for two decades. It worked perfectly for her personality and cognitive style. Sarah's approach felt like being forced to write with her non-dominant hand.

But here's the thing that really gets me wound up: most supervisory training programs completely ignore this psychological reality. They focus on policies, procedures, and legal compliance. Important stuff, sure, but it misses the fundamental challenge of supervision.

The challenge isn't knowing what to do. It's knowing how to help other people do it.

I've run workshops where participants can recite performance management procedures backwards but couldn't motivate a team member if their job depended on it. Which, ironically, it does.

The best supervisors I've worked with—and I mean the genuinely exceptional ones—share a common trait that has nothing to do with their previous job performance. They're genuinely curious about how other people tick. Not in a manipulative way, but in an authentic "I want to understand what makes you successful" way.

Take Marcus, a former electrician who became a site supervisor for a major construction company in Perth. His technical skills were solid but not spectacular. What made him exceptional as a supervisor was his ability to recognise that his apprentices learned differently than he did.

Where other supervisors would get frustrated with apprentices who needed visual demonstrations rather than verbal instructions, Marcus would grab his phone and record quick video tutorials. Problem solved.

Simple? Yes. Revolutionary? Apparently.

The construction industry is notorious for the "sink or swim" approach to training, but Marcus understood something his colleagues missed: different people need different types of support to succeed. His team had the lowest turnover rate in the company and consistently delivered projects ahead of schedule.

Here's another thing that drives me crazy about traditional approaches to professional development: they treat supervision as a set of skills rather than a mindset shift.

Skills can be taught in a weekend workshop. Mindset shifts take months of practice and reflection.

The mindset shift is this: your job is no longer to be the best individual contributor. Your job is to help other people become the best individual contributors they can be. That's not just a different skill set—it's a completely different way of thinking about work.

Sarah eventually figured this out, but it took six months of coaching and some brutally honest feedback from her team. The breakthrough came when she stopped trying to clone herself and started focusing on what each team member needed to succeed.

One team member needed more structure and regular check-ins. Another needed more autonomy and creative freedom. A third needed explicit recognition for good work—something that had never mattered to Sarah personally but was crucial for that person's motivation.

The transformation was remarkable. Within three months, her team's productivity was 40% higher than when she'd been trying to impose her personal system on everyone.

But here's what really annoys me about this whole situation: it was completely predictable and entirely preventable. Companies know that technical competence doesn't guarantee supervisory success, yet they keep making the same promotion mistakes over and over again.

Why? Because it's easier to promote the obvious choice than to do the hard work of identifying supervisory potential.

Real supervisory potential looks different than you might expect. It's the person who notices when a colleague is struggling and offers help without being asked. It's the team member who can explain complex concepts in simple terms during training sessions. It's the individual who naturally gravitates toward collaborative solutions rather than competitive ones.

These behaviours are observable and measurable, but most companies don't bother looking for them. They promote based on sales numbers, technical certifications, or length of service.

The result? A epidemic of accidental supervisors who are set up to fail from day one.

I'm not suggesting that technical competence doesn't matter. Obviously, supervisors need to understand the work they're supervising. But technical competence should be the baseline requirement, not the primary selection criterion.

The primary criterion should be demonstrated ability to help other people succeed.

And for those companies that do identify supervisory potential early, the benefits are enormous. Teams with good supervisors have higher retention rates, better performance metrics, and significantly lower stress-related sick leave. The ROI on proper supervisor selection and training is somewhere around 300%, according to recent studies.

Yet most companies still treat supervision as an afterthought—something people will figure out on the job.

They wouldn't expect someone to perform brain surgery without proper training, but they'll put someone in charge of a dozen employees with nothing more than a congratulatory handshake and a new parking space.

The good news is that supervisory skills can be developed, even in people who don't have natural talent for it. But it requires intentional effort and proper support, not just wishful thinking.

Sarah now runs her own training sessions for new supervisors, focusing specifically on the psychological aspects of team management. Her favourite exercise involves having participants shadow different team members for a day, just observing how they work and what they need to be successful.

It's a simple exercise, but the insights are profound. Participants consistently report that they had no idea how differently their team members approached the same tasks.

That awareness is the foundation of effective supervision.

The bottom line is this: if you're promoting people based solely on their individual performance, you're doing it wrong. And if you're expecting new supervisors to figure it out on their own, you're setting them up to fail.

Good supervision isn't accidental. It's intentional, learnable, and absolutely critical to business success.

The question is: are you willing to invest in developing it properly?