Interviewer view · keep this screen to yourself
Spans and layers at a UK retailer's head office
You run the case. Read the prompt, answer questions from the notes below, and share data only when the candidate asks for it or gets stuck. Score at the end.
Case timer
00:00
1. Read the prompt aloud
Read it slowly, then pause. Let the candidate ask questions before they structure.
A UK retailer's head office has 1,200 people reporting to 240 managers. The average manager costs GBP 80,000 a year. The exhibit shows spans by function. Does it have too many managers, and what could it save?
Format note: Interviewer-led: the interviewer shows the span table and asks for the size of the opportunity.
2. Answers to clarifying questions
Give these answers only if the candidate asks. If they ask something not listed, give a sensible answer or say it does not matter here.
If asked: Does everyone counted report to one of the managers listed?
Answer: Yes, 1,200 people report to 240 managers.
If asked: What span fits this work?
Answer: Similar head offices run about 8 for routine work, which covers most of finance, HR, and marketing here, and 5 to 6 for specialist work such as IT.
If asked: What happens to people in removed manager roles?
Answer: About half would move into specialist roles at similar pay; the rest would leave.
3. The hypothesis a strong candidate states
Listen for an early, testable guess like this one. It does not need to match word for word.
An average span of 5 is narrow for a head office with a lot of routine work, so my hypothesis is that there are too many managers, but that the real saving is smaller than the headline because many managers would move into specialist roles.
4. A model structure
Compare the candidate's structure with this one. A different split can be just as good if it is clean and fits the problem.
- Spans versus the type of workThis comes from managers needed = people / target span, and the saving = managers removed x cost per manager.
- Average span today
- Managers needed at a target span
- Key: Realistic saving
- Where to start: function spans
Exhibit 1
Reveal to candidate: when they ask for this data, say "Open Exhibit 1" (they press "Show exhibit 1" on their screen).
| Function | People reporting to managers | Managers | Average span |
|---|---|---|---|
| Finance | 300 | 60 | 5 |
| HR | 150 | 50 | 3 |
| IT | 450 | 75 | 6 |
| Marketing | 300 | 55 | 5.5 |
So-what
HR has the narrowest spans and much routine work, so it is the first place to look. IT is closest to a sensible span for specialist work.
5. The working, step by step
Each step shows how a strong candidate works it out. Share a new fact from it only when the candidate asks or is stuck, and let them do the math: the result in the dark box is what they should reach.
Step 1: Average span today
What a strong candidate does: Direct reports divided by managers.
Average span: 1,200 ÷ 240 = 5
Step 2: Narrowest function
What a strong candidate does: HR has 150 people reporting to 50 managers, the narrowest span in the exhibit.
HR span: 150 ÷ 50 = 3
Step 3: Managers needed outside IT at a span of 8
What a strong candidate does: IT does specialist work, so it keeps its span of 6 and its 75 managers. The other 750 people do mostly routine work and can move to a span of 8.
Managers needed outside IT: (1,200 - 450) ÷ 8 = 93.75
Step 4: Manager roles removed
What a strong candidate does: Compared with the 165 managers outside IT today.
Roles removed: (240 - 75) - (1,200 - 450) ÷ 8 = 71.25
Step 5: Headline saving
What a strong candidate does: If every removed role left the company.
Headline saving (GBP a year): ((240 - 75) - (1,200 - 450) ÷ 8) × 80,000 = 5,700,000
Step 6: Realistic saving
What a strong candidate does: About half move into specialist roles at similar pay, so only half the cost leaves.
Realistic saving (GBP a year): ((240 - 75) - (1,200 - 450) ÷ 8) × 0.5 × 80,000 = 2,850,000
The recommendation to listen for
At the end, say: "The CEO walks in. What is your recommendation?"
Yes, the head office has too many managers, and the realistic saving is about GBP 2.85 million a year, not the headline GBP 5.7 million. First, the average span is 5 and HR's is only 3, narrow for largely routine work. Second, moving the 750 people outside IT to a span of 8 needs about 94 managers instead of 165 today, removing about 71 roles, but about half those managers would move into specialist roles, so only half the cost leaves. Third, IT does specialist work and should keep its span of 6. Start with HR and finance processing, redesign decision rights at the same time so fewer layers also means faster decisions, and communicate early to keep good people.
Risks a strong answer names: Too-wide spans for complex work can hurt quality; Good managers may leave if the process is unclear; Savings shrink if removed roles come back over time.
Next steps: Classify each team as routine or specialist and set target spans; Redesign HR and finance processing first; Track manager numbers quarterly.
Strong versus weak
A strong answer
Measured spans by function, matched target spans to the type of work, and turned the headline into a realistic saving.
A weak answer
Applied a span of 10 to every team and claimed the full headline saving.
Score the candidate
Score each criterion from 1 to 5. A 2 or a 4 sits between the descriptions.
Total
0 out of 25
Score all five criteria to see the band and the feedback template.