Profit and cash do not arrive together
Making something means buying materials, and that money leaves immediately. While the finished goods sit in a warehouse nothing comes back. When they sell, revenue is recognised — but the cash usually arrives 30 to 60 days later. The cash conversion cycle is that whole stretch, less however long the company takes to pay its own suppliers.
A long cycle means growth consumes cash. This is the standard way a growing company runs out of money: orders rise, inventory and receivables rise with them, and the extra working capital is needed before the collections arrive. The income statement shows a profit while the bank account empties.
Inventory and payables divide by cost, not by sales
The three denominators differ for a reason. A receivable is what was billed at the selling price, so it divides by revenue. Inventory and payables are carried at cost, so they divide by cost of revenue. Each matches the basis the balance sheet figure was recorded on.
Dividing all three by revenue is a common shortcut, and it makes both inventory days and payable days look shorter than they are — by half, for a company on a 50% gross margin. The two errors partly offset in the total, but the individual figures are then not readable.
Working from quarterly figures, change the day count to 90 or 91. Leaving 365 in place multiplies every result by four. Annualising the quarter instead — multiplying the flows by four and keeping 365 — also works, but in a seasonal business the annualisation is itself the distortion: run a retailer’s first quarter through it and the inventory days come out far longer than the year actually is.
A negative cycle
A negative cycle means customers pay before suppliers do. The working capital is being funded by the supply chain rather than by the company, and growth generates cash instead of consuming it. Large retailers and some e-commerce businesses run this way.
It comes from bargaining power: suppliers accept 90-day terms because they cannot afford to walk away. So a negative cycle measures market position as much as efficiency. And when payable days stretch suddenly, it can mean either that the company has become harder to refuse or that it is short of cash and paying late. Both look identical in the number.