That's right. Non-cash increases in working capital assets are deductions from operating cash flow, reflecting the fact that you have to pay cash for the new goods.

Companies can finance by borrowing, either from suppliers (e.g. payables) or lenders, which appears as sources of cash. But if the debt is long-term that cash appears elsewhere on the cash flow statement and so don't counterbalance the use of operating cash.

Why is operating cash important? Investors focus on it because that's how companies make money. Investing cash flow reflects hard-to-repeat asset sales, financing cash flows must be repaid. And it's hard to game operating cash flow without raising flags elsewhere.

But here the financial analysis is more important for its signals of marketing and operational strength.

Apple can't maintain low inventories, especially while growing revenue, without knowing its market pretty well. And low inventories mean it doesn't cost them much to obsolete their own products, and doesn't cost them as much to try products that don't work out. The dollars saved by low inventory don't mean so much relative to the overall enterprise, but they can't keep this metric low without real strength up and down the company.