Recognition and measurement
If there were no rules or principles then assets, liabilities, income and expenses could be recognized at possibly justifiable different times and values measured at justifiably different amounts. GAAP frameworks and standards define recognition and measurement in some detail.
Recognition of assets
An asset is recognized in the balance sheet when it is probable that the future economic benefits will flow to the entity and the asset has a cost or value that can be measured reliably.
Recognition of liabilities
A liability is recognized in the balance sheet when it is probable that an outflow of resources embodying economic benefits will result from the settlement of a present obligation and the amount at which the settlement will take place can be measured reliably.
Recognition of income
Income is recognized in the income statement when an increase in future economic benefits related to an increase in an asset or a decrease of a liability has arisen that can be measured reliably.
Recognition of expenses
Expenses are recognized in the income statement when a decrease in future economic benefits related to a decrease in an asset or an increase of a liability has arisen that can be measured reliably. This means, in effect, that recognition of expenses occurs simultaneously with the recognition of an increase in liabilities or a decrease in assets (for example, the accrual of employee entitlements or the depreciation of equipment).
When economic benefits are expected to arise over several accounting periods and the association with income can only be broadly or indirectly determined, expenses are recognized in the income statement on the basis of systematic and rational allocation procedures. This is often necessary in recognizing the expenses associated with the using up of assets such as property, plant, equipment, goodwill, patents and trademarks; in such cases the expense is referred to as depreciation or amortization.