The decrease of an asset does not result in the recognition of income; expense is recognized when you decrease an asset. If we think in terms of a journal entry, what do we do to decrease an asset? We credit the asset to decrease it and must debit some other account–usually an income statement (P&L) account; therefore a debit to an income statement account immediately means “expense.”
Let's use the inventory asset example you mention above. If we have $5,000 of inventory on hand at 12/31/12, and our physical inventory count reveals only $3,000, what do we do? We must “write-down (decrease) inventory from $5,000 to $3,000, which would result in $2,000 of expense being charged to COGS. Make sense? Based on what I am reading above, you are getting confused between revenue being generated from decreasing an asset (like inventory) and the literal accounting of a decreasing asset, irrespective of the revenue it may generate.
Let's discuss how the decrease of a liability results in the recognition of revenue. We know that liabilities on a balance sheet carry a normal credit balance. When a liability is established, we more-often-than-not debit some type of expense on the income statement. Say, at 12/31/12 we had accrued rent of $10,000. When analyzing this balance sheet account during the month-end close process, we realized that we had overaccrued by $5,000. What do we do? We must debit accrued rent for $5,000 and credit rent expense for $5,000 because we had too much $$ in the account at the end of the year. When we credit rent expense (P&L account), we have recognized income; yes, I know, you're stuck on the fact that we are crediting an expense account. You're thinking how can that be revenue–it is! Whenever you decrease expense, you are generating revenue (income). Again, you must come out of the literal sense of thinking to embrace this concept.
Let me know if I have confused you even more or if you need further clarification.
Texas CPA - licensed in 2012!!!
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