When Your Best Employee Starts Acting Like a Stranger: A Leader's Guide to Mental Health Red Flags

The resignation email landed in my inbox at 11:47 PM on a Thursday. Sarah, my top performer for three years running, was "pursuing other opportunities." No two weeks' notice. No handover notes. Just gone.

It wasn't until months later I realised I'd completely missed the signs. The gradual withdrawal from team meetings. The perfectionist who suddenly couldn't meet deadlines. The colleague who used to crack jokes during our Monday briefings but had gone silent for weeks.

Here's what nobody tells you about being a leader in 2025: you're not just managing spreadsheets and KPIs anymore. You're accidentally becoming the workplace's first line of mental health defence. And most of us are terrible at it.

The Uncomfortable Truth About Mental Health in Leadership

Look, I'll be straight with you. For years, I subscribed to the "leave personal stuff at home" mentality. Work was work. Home was home. Simple boundaries, right?

Wrong. Dead wrong.

Mental health doesn't clock out at 5 PM. It doesn't respect your carefully crafted org charts or your "professional environment" policies. It shows up in missed deadlines, in snap decisions that make no sense, in your usually reliable team member who's suddenly making basic errors.

The statistics are staggering. According to recent workplace studies, roughly 67% of employees have experienced mental health challenges that directly impacted their work performance. Yet only about 23% of leaders feel equipped to recognise and respond appropriately.

That gap? That's where good people fall through the cracks.

What Mental Health Actually Looks Like at Work

Forget the Hollywood version of mental health crises. Real workplace mental health issues are often subtle, gradual, and easy to misinterpret as performance problems.

Take anxiety. It doesn't always present as someone having panic attacks in the break room. More often, it's the employee who suddenly needs every instruction in writing. Who asks for clarification on tasks they've done hundreds of times. Who seems paralysed by decisions they used to make confidently.

Depression? It's not necessarily someone crying at their desk. It's the team member who used to contribute ideas in brainstorming sessions but now sits quietly. The person whose work quality hasn't dropped, but their engagement has flatlined. They're physically present but mentally... elsewhere.

And burnout - which I'd argue is the epidemic of our time - looks like someone working harder but achieving less. Like your star performer who's putting in 60-hour weeks but producing half their usual output. They're not lazy. They're running on empty.

The Leadership Trap We All Fall Into

Here's where most leaders stuff it up, myself included. We see the symptoms and immediately jump to performance management mode.

"Sarah's missing deadlines. Time for a formal improvement plan."

"Jake's not participating in meetings. He must have lost interest in his role."

"Emma seems stressed all the time. Maybe she's not cut out for this level of responsibility."

We pathologise the behaviour instead of recognising it as a potential cry for help. We treat the symptom instead of considering the cause.

I remember having a conversation with my own manager about this years ago. He told me something that stuck: "Good leaders don't just manage the work. They manage the whole person who does the work."

Sounded like HR fluff at the time. Now I realise it's probably the most practical advice I've ever received.

Building Your Mental Health Radar

The best leaders I know have developed what I call "mental health radar." They notice changes in patterns before they become problems.

Check-in conversations matter more than you think. Not the formal quarterly reviews. I'm talking about the casual "How are you actually going?" conversations. The ones where you're genuinely listening to the answer, not just waiting for your turn to talk about the quarterly targets.

Watch for changes in communication patterns. Your chatty team member goes quiet. Your quiet team member suddenly becomes overly talkative. Your detail-oriented person starts missing obvious things. These shifts often signal something deeper.

Notice the little things. Someone who's usually first in the office starts arriving just on time. The person who never takes sick days suddenly takes three in two weeks. Small changes can indicate big struggles.

The key is baseline awareness. You need to know what normal looks like for each team member before you can spot when something's off.

The Conversation Nobody Teaches You How to Have

"I've noticed you seem a bit overwhelmed lately. Want to talk about it?"

Sounds simple, right? It's not. These conversations are awkward, messy, and require you to shut up and listen more than you talk.

First rule: don't try to fix everything. Your job isn't to be a therapist. Your job is to be a supportive manager who recognises when professional help might be needed.

Second rule: focus on work impact, not personal diagnosis. "I've noticed your usual attention to detail seems stretched thin lately. Is there anything I can do to help you manage your workload?" Not "Are you depressed?"

Third rule: have resources ready. Know what your EAP program offers. Understand your company's mental health policies. Have contact information for local mental health services. Don't just identify the problem - help create pathways to solutions.

The Business Case for Caring

Let me put this in terms every leader understands: dollars and productivity.

Replacing a good employee costs anywhere from 50% to 200% of their annual salary. Training their replacement. Lost productivity during the transition. The impact on team morale. The knowledge that walks out the door.

Early intervention on mental health challenges isn't just the right thing to do - it's smart business.

Companies with strong mental health support report 21% higher productivity, 37% better sales performance, and three times more likely to retain top talent. These aren't feel-good statistics. This is bottom-line impact.

But here's what really drives the point home: when you create an environment where people feel safe to struggle, they're more likely to ask for help before things reach crisis point. Prevention is always cheaper than crisis management.

What Support Actually Looks Like

Real mental health support isn't ping pong tables and meditation apps. Though those don't hurt.

It's flexible work arrangements that acknowledge people have different needs and different peak performance times. It's recognising that sometimes the best thing you can do for an overwhelmed employee is to temporarily reduce their workload, not pile on more "development opportunities."

It's training yourself and your leadership team to recognise warning signs. It's having difficult conversations with compassion instead of judgement.

And sometimes - this is crucial - it's knowing when to recommend professional help and how to do it without making someone feel like they're being managed out.

The Ripple Effect

When Sarah left that night, it affected more than just her role. The team spent weeks trying to cover her responsibilities. Two other team members became visibly stressed. Morale took a hit that lasted months.

But here's what I learned: one person's untreated mental health challenges can impact an entire team's wellbeing. Creating a supportive environment isn't just about individual care - it's about protecting your whole team's mental health.

The leaders who get this right don't just have better retention rates. They have teams that support each other, that speak up when they're struggling, that see mental health as just another aspect of workplace safety.

Making It Real

Start small. Pick one team member you're genuinely concerned about and have a real conversation this week. Not about their productivity metrics. About how they're going.

Listen more than you talk. Ask what support would actually help. Don't assume you know what they need.

If you're in Perth, there are excellent workplace abuse training sessions that can help you recognise broader workplace mental health patterns. For more comprehensive leadership skills for supervisors, invest in training that covers these scenarios.

The uncomfortable truth is that mental health awareness for leaders isn't optional anymore. It's a core leadership competency. The leaders who master it will have the strongest, most resilient teams. The ones who ignore it will keep losing good people and wondering why.

Your people are watching how you handle these situations. They're deciding whether your workplace is somewhere they can be human, make mistakes, struggle, and still be supported.

What message are you sending?