Take a look at a balance sheet and an equity statement. A number of those items require full and complete financial information to be accurate. An income statement is a snapshot of the 2 (or 3) years covered by the date of the statement, but a balance sheet and equity statement are since inception. If information is missing, it is impossible to present those statements accurately. Even 1 year's information that is missing can easily cause the financial statements to not be accurate, and therefore not auditable.