Do you use the accrual method of accounting? If so, any increase in inventory must be subtracted from your accrual net profit amount to determine your net cash flow profit. The increase in inventory represents an expense that was paid but not yet subtracted from your accrual net profit. Under the mechanics of accrual accounting, the purchase of inventory is not considered to be an expense until the inventory is sold. In terms of a cash flow, you've already paid for the inventory; therefore, it must be subtracted from your accrual net profit.
Similarly, a decrease in your inventory amount must be added to your accrual
net profit to determine your net cash flow. The decrease in inventory represents
an expense subtracted from your accrual income to determine your accrual net
profit. However, no cash left your business in this accounting period for the
expense reflected by the decrease in inventory.