A business leader told me this week that the average tenure in their lowest-paid roles is less than twelve months. They mentioned it almost in passing.

The maths behind that tells a powerful story.

The CHRO’s problem

If you lead People & Culture, you already know why engagement matters. You’ve seen the survey results, you know which teams are struggling and more importantly why, you’ve (re)built the programme. You’ve got internal comms, management training, and a spotlight on purpose and benefits, and you believe in it.

The blocker is often Finance.

They’re not wrong to ask questions, but the answers are tricky. The conversation usually goes like this: you present the engagement data, you make the case for investment, and somewhere around slide four, their eyes glaze over. The soft stuff, hard to measure, “nice to haves” (I’m not a big fan of that phrase…).

The conversation can take a different course: disengagement is a cost problem, and whether you run the numbers or not, you’re already paying for it.

The maths which will get the CFO’s attention

Take a supply chain business. £200m revenue. 1,500 employees. Roughly 70% operational and warehouse staff, the rest in management and office roles.

Attrition in that kind of business runs high, particularly at the operational end. Assume 25% turnover among warehouse staff and 12% among the management population. That’s 317 people leaving every year.

Now put a cost on each departure. Recruitment, onboarding, the productivity gap while a replacement finds their feet. A conservative estimate would be: £5,000 per operational leaver, £15,000 per management leaver.

The annual attrition bill comes to roughly £2.1 million.

Many CFOs may not have seen that number written down. They might feel it in agency costs, management time, and the low hum of operational disruption, but they haven’t rolled it into one number. So do it for them.

Show the threshold, not the proof

Now we introduce the intervention: an employee engagement programme with internal comms and management training, built off the latest staff survey results. Total cost: £85,000.

That’s 4% of the annual attrition bill.

To find the break-even point, divide the programme cost by the blended average cost per leaver across both staff groups. That blended figure works out at £6,697. Divide £85,000 by that and you need to retain just 13 people who would otherwise have left.

Thirteen people is fewer than one in twenty-five of those at risk of leaving. Less than one percentage point reduction in overall attrition.

When the average tenure in your lowest-paid roles is less than a year, is it plausible that a well-designed engagement programme could change that for 13 people?

Almost certainly yes.

You’re not claiming it will deliver a specific outcome. You’re showing what it needs to deliver for the investment to make sense. The bar is visible. The audience can judge for themselves.

And when they do, the answer is obvious.

What the numbers don’t capture

The maths gets you through the door, but that doesn’t mean you leave the human argument in reception.

Thirteen people retained is also thirteen people who didn’t burn out and leave. Thirteen managers who didn’t spend a month recruiting and onboarding someone new. Thirteen gaps that didn’t quietly erode team morale for the colleagues who stayed.

Low engagement compounds. The people who leave are visible on the attrition report. The people who stay but stop caring are harder to count, but your CFO knows they’re there, even if they won’t say so.

Run the attrition numbers and the CFO sees a cost argument. But the engagement programme sends a broader signal: that leadership is paying attention.

A method you can use

If you’re building a people and culture case for a sceptical finance audience, here’s the approach.

1. Start with the cost of your intervention

2. Calculate the full annual attrition cost: recruitment, onboarding, lost productivity

3. Express the programme cost as a percentage of that bill

4. Show the threshold: how many retentions does it take to break even?

5. Show that is number small: per team, per month, as a fraction of total leavers

6. Then show what retention produces beyond the spreadsheet: stability, morale, capacity

The CFO needs the numbers, but they also need to believe the bar is reachable. Your job is to show them both.

Over to you!

Where are you struggling to make the people case? Is it attrition, engagement, or something harder to pin down, like the cost of a team that’s technically present but quietly checked out?

Always good to hear what you think!

I spent twenty years in senior leadership roles at Sky, ITV, NBC News and Future Plc before becoming a Consulting Partner at Positive Momentum, where I advise organisations across financial services, sustainability and technology on strategy, storytelling and change. Impact Storytelling sits at the centre of that work.

Calculations

Operational leavers: 1,050 × 25% = 263 × £5,000 = £1,312,500

Management leavers: 450 × 12% = 54 × £15,000 = £810,000

Total: 317 leavers, £2,122,500 (≈£2.1m)

Blended average cost per leaver: £2,122,500 ÷ 317 = £6,697

Retentions needed to break even: £85,000 ÷ £6,697 = 12.7, rounded to 13

13 ÷ 317 = 4.1% of annual leavers (fewer than 1 in 25)

13 ÷ 1,500 = 0.87% of total workforce (less than one percentage point reduction in attrition)