Almost every resignation comes as a surprise to the manager. Almost no resignation is actually a surprise.

The signs that someone is on their way out start months - sometimes years - before the resignation letter. Most managers either do not see them, or see them and do not know what to do. Either way, by the time the conversation is being booked in a calendar invite titled "Quick chat", it is usually too late.

Why this matters more than it used to

Replacing a mid-level employee can cost a substantial share of their annual salary once you factor in recruitment, onboarding, training, lost productivity and team disruption. For senior or specialist roles the figure climbs significantly higher. And those numbers do not capture the harder-to-measure cost of losing institutional knowledge, breaking team rhythms, or signalling instability to the people who stay.

If you can identify and address disengagement six months before someone resigns, the maths is overwhelming. Even a moderate retention improvement transforms the economics of your team.

The early signs (subtle but real)

Withdrawal from optional things

The team lunch they always came to, the social Slack channel they used to be active in, the knowledge-sharing session they used to volunteer for. These start to drop off long before formal performance changes. People withdraw socially before they withdraw professionally.

Reduced ambition signals

The colleague who used to put their hand up for stretch projects stops volunteering. They no longer mention career goals. Their development conversations get shorter, more polite, less specific. They are still doing their job - but they have stopped imagining a future doing it.

"Good enough" output

The work still gets done, but with less of the polish that used to be there. Fewer suggestions in meetings. Less initiative on edge cases. The standard hits the bar but never exceeds it. They are doing the job, not investing in it.

Quiet credential building

They start finishing online courses they never mentioned. They suddenly have a polished LinkedIn profile. They are quietly preparing.

The middle signs (harder to ignore)

Calendar pattern changes

Mid-week appointments at unusual times. More working from home days clustered together. Long lunches. None of these are smoking guns individually, but the pattern is recognisable in retrospect.

Changing relationships

They stop sharing professional opinions in meetings. They become more transactional with colleagues they used to be close with. They stop pushing back on things they used to challenge. They are protecting themselves from emotional investment.

Asking for confidential references

You will not see this directly, but it is a near-certain leading indicator. If they have asked someone for a reference, they have probably already applied for at least one role.

The late signs (probably too late)

  • Suddenly very polished, professional appearance for video calls
  • Notably better mood overall - they have made the decision and feel relieved
  • Reluctance to commit to anything beyond a few weeks ahead
  • "Just exploring options" mentioned in passing

What to do (without being weird about it)

Have real conversations earlier

Most disengagement could be addressed if it was caught early. Many people who leave would have stayed if someone had asked them, in a real and unhurried way, what was actually going on. Not the formal review. A genuine conversation. They are remarkably rare.

Show development paths concretely

The most common answer to "why are you leaving?" is some version of "I could not see where I was going next." If your team can see exactly what skills they would need to develop for the next role, what support is available, and what timeframe is realistic, that conversation looks very different.

Surface and use their wider skills

Disengaged employees often have skills the organisation never asked them to use. The chef trained in pastry frying chips. The engineer who used to do video editing stuck on tickets. Discover those skills, and you can find ways to deploy them - which is one of the most powerful retention moves there is.

Stop assuming pay is the answer

It usually is not. Counter-offers rarely retain leavers in the long term - the recruitment-industry consensus is that most people who accept one leave within twelve to twenty-four months anyway. The thing that retains people is feeling seen, valued, and like they have somewhere to go - all of which money does not buy.

The fundamental truth

People leave managers, not companies. And they leave when they stop being seen. The single best retention strategy is making sure nobody on your team feels invisible - not their work, not their potential, not the wider capabilities they bring to the job.

That is harder than it sounds. But it is also achievable, and it is dramatically cheaper than the alternative.