Warehouse automation payback: include the ramp and real savings

The interviewer shares Exhibit 1: the automation proposal’s cash inputs. Savings are incremental cash savings relative to continuing the current operation. Ignore tax, financing and working capital for this exercise.

Assume cash savings and maintenance accrue evenly within each year. The question is whether the proposal meets the payback requirement, and what would need to change if it does not.

Calculate the payback period before reading the worked solution.

Year one generates £30,000 − £10,000 = £20,000. Each later year generates £60,000 − £10,000 = £50,000.

The cash-recovery schedule below is calculated from those inputs. It tracks cumulative benefit against the original £120,000 investment.

Simple payback is three years. It misses the client's 2.5-year requirement by six months.

There are two tempting shortcuts. £120,000 ÷ £60,000 gives two years, ignoring maintenance and ramp-up. £120,000 ÷ £50,000 gives 2.4 years, including maintenance but still treating year one as fully productive. Both would incorrectly approve the proposal against this hurdle.

When annual benefits differ, add the cash flows in order. The timeline determines when the investment is recovered.

By 2.5 years, the project generates £20,000 in year one, £50,000 in year two and £25,000 during half of year three: £95,000.

At the stated savings, upfront cost would need to fall to £95,000 or less, a reduction of £25,000, to meet the hurdle.

Alternatively, hold upfront cost at £120,000 and keep first-year net benefit at £20,000. There are 1.5 years of mature operation before the deadline. Required mature annual net benefit is:

(£120,000 − £20,000) ÷ 1.5 = £66,667.

With annual maintenance still £10,000, gross mature savings must reach about £76,667, roughly £16,667 above the proposed £60,000. This is a more demanding operational target than saying “we need slightly better savings”.

These are separate scenarios. If changing the equipment price also changes maintenance or productivity, rebuild the relevant cash flows instead of combining favourable assumptions casually.

The prompt explicitly supplies cash savings. In a less complete case, the supplier might promise labour hours released, faster picking or higher throughput. Translate those benefits before putting them in the payback calculation.

If existing staff remain on the same payroll, released hours are capacity. They become a cash saving when they reduce overtime, temporary labour or a hire that would otherwise be needed. They can also create value by serving additional demand, but that value requires the extra contribution and any costs of doing so.

Avoid counting the same hours twice. You cannot treat all released hours as eliminated labour spending and simultaneously use those same hours to generate extra output.

Use the pilot to establish which cash costs disappear and whether the equipment can handle the expected order mix. Match the technology to the operating need.

For a downside scenario, return to the original £120,000 proposal, without either negotiated improvement. Suppose gross savings reach only 80% of plan while maintenance remains £10,000. First-year net cash becomes £24,000 − £10,000 = £14,000; mature annual net cash becomes £48,000 − £10,000 = £38,000.

After three years, cumulative benefit is £14,000 + £38,000 + £38,000 = £90,000. Another £30,000 remains. At £38,000 annually, recovery takes another 30 ÷ 38 of a year, giving about 3.79 years in total.

The 20% shortfall in gross savings creates a larger proportional deterioration in net benefit because maintenance does not fall with it. That is why I would test recurring costs and achievable savings separately.

A strong answer is:

“The proposal pays back in three years, outside the 2.5-year requirement. I would not approve it on the current economics. We need upfront cost at or below £95,000, or materially greater cash savings. A pilot should verify avoided labour spending and performance across our actual order mix before we renegotiate or redesign the project.”

Passing a simple-payback hurdle would still leave questions about equipment life and later cash flows. If the client asks which option creates the most value, compare the full relevant cash flows and use discounting when required. Do not quietly turn the recovery calculation into a claim about overall investment return.

Try the warehouse automation drill next. Write the timeline, calculate net cash and give the decision before discussing implementation details.